The 17-Pounder's Accuracy, and other things.

[@chuckw1113]

Interesting discussion. The following is purely anecdotal, but it’s based on my experiences as a cadet tanker at VMI and an armor officer on active duty starting in 1975. In my days at VMI (1971-75) the VMI Army ROTC program had two years of basic skills training, and then you “branched” the remaining two years into a combat arm. The branches offered were Infantry, Armor and Field Artillery. I opted for armor. At that time we were taught that US Army armor doctrine stated that the preferred antitank round was HEAT, and APDS (Sabot) was acknowledged as existing round but to be avoided due to problems with the ammunition itself. This was the Gospel according to Knox. When I arrived at FT Knox for Armor Officer Basic in ‘75, the Army was undergoing a doctrinal shift. After reviewing the Israeli experience in the ‘73 War, the US Army was now advocating APDS as the standard antitank round, with HEAT also carried, but was to be used primarily against Infantry Fighting Vehicles and Armored Personnel Carriers. The reasons were many, but included the adoption of the “battlesight” engagement technique. The Israelis found that in their 105mm M48s they could index APDS with a range of 1500 meters in the ballistic computer, and when laying the sight on the base of the target they were always guaranteed a hit if the target was at 1500 meters or less. The change was also based on the APDS round itself. It seems that when the US first adopted the 105mm M68 gun (the American designation for the 105mm L7 Gun) they had a terrible time with APDS ammo. The main problem was with the Sabot separation, which caused a large number of stray rounds (called “fliers”), being wildly off target. At least this is what we were told. Since it was early in the development of the gun it’s possible there was a design issue with the round, and at that time most of the ammo was supplied by the UK. Whatever the problem was it was obviously fixed before the Israelis fought in 1973. In any event, the US Army changed its ways. We adopted the battlesight engagement technique and started training firing most engagements with Sabot. Our instructors there did acknowledge the issue of sensing the Sabot round as it went downrange, since the round was traveling at over 5000 FPS. Interestingly, on the range at Knox we did see a pair of “fliers” where the Sabot rounds went wildly off target and were told the round still had some separation issues. The US Army developed its APFSDS long rod penetrator, made of DU a few years later, and that put to bed any issues with the older APDS design.

[@pipss2669]

Given the massive model of it on your desk, will you make an "inside the hatch" video of the Consitution-class Starship Enterprise ?

[@Solidboat123]

"Oh my God, the starship is on fire!"

[@richardm1062]

Today a Constitution class starship model, last video he made a Locutus reference. I think there's a Trekker within that tanker that's struggling to get out.

[@SonsOfLorgar]

@chris younts but no bathrooms XD

[@tasman006]

Spock use the 90mm gun not the 17 pounder. Reminds me of the episode where Captain Kirk and Spock help topple on another planet a Nazi government started by one of there own a few years earlier because in historically it was the most successful type of government from res-session to a booming economy with plenty of jobs for all. Well pre war anyway. The episode is called Patterns of force hear is a little taste loved the old series for the Lols. kzbin.info/www/bejne/rqibn59rpr1peKc

[@llllib]

If you can provide one, I'm sure he would do it :-D

[@boxwoodgreen]

My late dad commanded a anti-tank artillery coy attached to a Canadian Infantry Regiment. He was wounded by a sniper after the company got their guns across a dutch canal Apr8/45. Holland has a lot of canals. That crossing task was a snipers dream range. Just as an aside pre-war my dad was a Sgt. in the local militia, the 26thField Battery R.C.A. One of the then privates in the Battery, eventually became a Starship Chief Engineer.

[@stephenland9361]

Life and fiction are full of surprises. Chief Engineer Montgomery "Scotty" Scott of Star Trek fame was supposed to be Scottish. He was in fact a Canuck, born in Vancouver BC. Born James Montgomery Doohan, he wasn't even of Scottish ancestry. Both of his parents were from Northern Ireland. While he was an artillery officer, he was also a pilot. He flew the Taylorcraft Auster Mark V aircraft which was a small observation, spotter and liaison plane. He once slalomed the thing between telephone poles just to show that it could be done. He went ashore at Juno Beach on D Day. That evening he was hit by a burst from a machine gun, being hit six times; four to his leg, one to his right middle finger and one to the chest. The shot to the chest was stopped by a cigarette case. And oh, the gunner was a fellow Canuck weilding a Bren gun!

[@boxwoodgreen]

@@stephenland9361 Jimmy was born in Vancouver B.C. but his family moved to my hometown Sarnia, Ontario when he was an infant. He was on the Sarnia Collegiate (high school) rifle team with my dad. My late dad was an ancestral Scot, and was commissioned in the Essex Scottish regiment. My best friend was organizing our High School's 75th anniversary for 1996, and contacted Jimmy to invite him. He turned down expenses offered, and came on his own. I was honoured to meet and talk with him. He was a true gentleman.

[@jonmce1]

My dad drove tank from Monte Casssino up through Italy and then Belgium and Holland. You would never be able to convince him with any late claimed analysis that at least in the Canadian army they were damned glad to have them and that the Germans feared them enought ot specifically target them which is why they never allowed their 17ib sherman( I never heard him call it a firefly.) to lead the troop. Additonally the 17lb sherman took out more Tiger tanks in 15 minutes than the Americans did while in Northern Europe. The British did an evaluation of the 76mm and because of what they considered its deficiencies did everything they could to jam the 17ib into other tanks. They saw it in trils well before it went into production.

[@christineshotton824]

I'm just geeking out about the fact that I have the same NCC1701C Enterprise miniature as is featured front and center on Nick's desk.

[@scottcampbell2836]

Barrrel harmonics can spread the groups out on long barrels. With a rifle cutting and re crowning it untill you find the sweet spot with the ammo used. Lightweight projectile and long barrel prone to barrel whip makes wobbly shot grouping.

[@knutdergroe9757]

I will bet, Rifle twist is a big factor here. Especially in the sabo rounds. I have also found the power burn rates can effect group size as well.

[@ScottKenny1978]

Yes, the US 175mm artillery gun was notorious for barrel whip throwing rounds off, particularly at long range.

[@keithdurose7057]

The barrel whip syndrome led to the production of the thermal sleeve to help reduce its effect. Long barrels and tiny projectiles may be why the M4 may be better than the M16? Adding in the unpredictability of discarding sabot. The chances for inaccuracies magnified.

[@637man3]

This was a great view on an iconic weapon system, I'm a Firefly fan even with the warts but was never really up on the gun's genesis. I did some scratching around, British Pathé did a piece on what appears to be training and use in Africa which was interesting and Matsimus showed the wheeled version off in great style. One thing I noticed as it's apropriate to the closing comments here, at 2:00 of Matsimus' presentation, the sliding breech block has "17PDR" clearly stamped in the metal. Yet the ammo crates have "17 PR" so it was probably the Ministry of War deciding to save money and paint by dropping a letter.

[@rdfox76]

The SVDS ammo situation sounds like something where a bit of communication with the blokes over in the Navy might have been helpful. See, in the interwar period, there were lots of experiments towards making naval guns more effective without actually changing the guns (to avoid violating treaty limitations), and one line of thought was that lightweight shells at super-high velocities, having more kinetic energy, would successfully punch through more armor than conventional shells. And it worked just fine--when they could score hits. However, the consequence of this super-high velocity was excessive dispersion (overly large groupings) that was eventually traced directly to the desire for high muzzle velocity. The random overweight/underweight of every individual shell, and the random burn characteristics of each individual powder charge, while still within the specifications, resulted in a larger *total* random variation from shot to shot with faster shells--it might still be, say, a 2% variation in muzzle velocity, but they found that when you're shooting at 3300 feet per second, that 2% is a significantly larger absolute number than 2% of 2700 fps, making the grouping bigger. (They discovered this only after eliminating problems such as aerodynamic interference between shells in a salvo, but that doesn't really apply to tanks.) The only solution found, at least back then, was to derate the guns back down to lower velocities with either heavier shells, smaller powder charges, or a combination of the two. (Shortly thereafter, someone realized that an extra-heavy shell, moving slower, tends to fall more vertically at the long ranges that new fire control systems made possible, and thus the trend actually went towards heavier, slower shells that would hit the decks at more favorable angles for penetration, as hitting the side was becoming less and less common.) I don't know what sort of technical wizardry they now use to get what seem impossibly long ranges out of modern naval guns with sufficient accuracy, but it seems like the 17pr's problem may well have been something the US and Royal Navies had both encountered and overcome in the late 20s and early 30s...

[@88porpoise]

Naval guns and AT Guns are very different beasts. Naval guns would be far more like the heavy howitzers than an AT gun, but they are on a completely different scale. The 17 pounder is a 3 inch caliber. The standard naval gun on destroyers and light gun on large ships would be 4-5 inch caliber. A superheavy gun was 9.2 inches with a 13km range a Iowa class 16 inch gun could hit targets over 30 km away with a shell ten times as heavy (approximately the same weight as a 17 pounder, in fact). The forces and situations facing these guns are very different.

[@alganhar1]

With normal shells yes, but SVDS was a sabot round, so while some of the innaccuracy probably is down to the factors you noted, much of it is down to the seperation of the sabot from the penetrator. When and how that happens is going to have a significant impact on accuracy. If the seperation is not smooth and effectively immediate when it occurs that is going to throw off the round. To my knowledge no navy really played around with Sabot rounds, not in a big way, a tank is different to a ship, a kinetic penetrator is more than capable of killing a tank, but in a much larger target such as a ship even a large penetrator may pass right through the ship without causing any significant damage. Which is why all Naval AP rounds carried a bursting charge fused to (hopefully) detonate within the target once the round had punched through the armour. That being said, the Comets 77 had no issues, so while I do think the velocity was the problem I am more inclied to think the velocity monkeyed with that sabot seperation in unpredictable ways, a thought that is potentially supported by the fact that the Canadian redesign of the sabot seemed to fix most if not all the issues.

[@olivialambert4124]

Modern guns use a lot of wizardry, mostly based around reducing drag. They all add up to quite the difference. Usually just the boat tail design works well and is now used in a huge variety of weapons from rifles to the largest artillery with the downside of increasing wear. Add the base bleed shells, a small tracer-like charge burning to create smoke (rather than light) to fill the space behind the shell and thus the drag from the low-pressure void sucking it backwards doesn't apply. Or in the rarest of cases rocket assisted projectiles, though the only class using them I can think of are USS Zumwalt. Also used on artillery though seemingly only to meet demanded NATO specifications, one would imagine adding a rocket increases dispersion a lot and its only recently the Zumwalt (and possible future artillery shells) have started to use guided shells to counter that dispersion. Interestingly after inventing all of that wizardry to create the Zumwalt's cannons so incredibly revolutionary and able to save money vs the $2 mil cruise missile launchings, they decided to not buy more than the first run of cannon shells and don't use the gun. I don't know why, it worked as advertised. I imagine they will realise it was the right idea in 20 years or so.

[@CS-zn6pp]

As the same ammo worked fine in the comet then it must be down to the installation of the gun on the firefly. If we had data from the tow guns it would also help as they had the same ammo and barrel length as the firefly with the comet using the same ammo out of a shorter barrel thus if the tow guns were more accurate then its mounting issue not a Sabo issue. I'm guessing here but my money would be on it being down to the round being a little too hot and causing the Sabo separation issues.

[@mississippirebel1409]

rdfox76 - Talking about light weight shells, they aren't very good at penetrating at longer distances because they lose their velocity very fast and don't have enough punch to get through thick armor. During WW2 the US was known for using it's heavy 16" shells. These heavy shells where just as powerful as the Japanese 18" shells. Plus accuracy wasn't really an issue either.

[@Autobotmech]

As always informative and entertaining, thanks Chieftain.

[@magecraft2]

Must admit I find the contention about this a bit odd, it was a Antitank gun forced into a tank that was too small for it as a reaction to the rare German uber tanks. It did its role but no way was it going to be as refined a system as tanks and guns that had been specifically developed and improved through the war. Personally I love the Firefly as a symbol of British wartime engineering :) they quickly developed a solution to a problem, it was not a perfect solution but a workable one and I suggest in wartime that may well be the right one.

[@LeicesterRaver]

Yup, post war the 20 pounder was developed as a stop gap before the better calibres came into force.

[@DC9622]

Robert Pettigrew Mr Fletcher explanation on Firefly kzbin.info/www/bejne/f5fbnpdjqrKIa7s . The US Army Ammunition Research and Development organisation produced a paper on the 76mm M1 in 2018 January which is on line. To paraphrase the conclusion, specifically to this, the British produced the allies best anti tank gun of the war with the 17 pounder. The focus is penetration, which is the point of these things.

[@wyverncoch4430]

@@DC9622 Surely the point these things must be to first get the round on target, then to penetrate. Though I must admit I'd be more than happy with a grouping of 8-9 inches at 1000 yards

[@DC9622]

Wyvern Coch indeed, the after action reports are in contradiction with the quoted tests. There are a number of actions where the Firefly engaged Panther and Tigers, the scientific reports quoted 88% success the 6 pounder was 90%. Bottom line the Chieftain quotes the US Army engaged 3 tigers included 1 in Italy. Normandy the commonwealth army claimed 135 Tigers. This was only possible because of the 17 pounder.

[@Lightwolf_VR]

Define claimed.

[@Caratacus1]

Your barn comment reminded me of a 21st Army group post-battle report. This identified a 17pdr shot that went straight through a soft skinned vehicle, and then on through a barn with 18 inch walls, and then through the front lower nose plate of a Panther which promptly blew up. See Holland's Normandy '44 book for details. So yes it apparently can hit a barn, and a truck, and still smash through the front turret of a Panther all at once.

[@mr.waffentrager4400]

Only 17 pounder or soviet 122 could do that ....not american 76

[@hoatattis7283]

caractucas: Yes this bloke is very biased to the Yanks. I will never watch him again

[@davidharvey8179]

@@hoatattis7283 how is stating facts from official reports biased? It was a balanced presentation on the 17 pdr compared to the usual ones you find.

[@agt155]

@@davidharvey8179 A very limited official report. This is much better. www.sfu.ca/~dmunro/images/accuracy.jpg

[@tobywenman4769]

@@hoatattis7283 he certainly does spout the virtues of American tanks often, however I believe he does genuinely believe all he says and is trying to do the right thing

[@jmullner76]

Better question: what does Ian's hair smell like? Cosmoline?

[@simonmorris4226]

Cordite!

[@Mirageknight2133]

Probably sprinkles of Tannerite in there too

[@sadwingsraging3044]

Incense and myrrh I suspect.

[@JonManProductions]

French Shampoo and Cologne.

[@natepatterson4934]

I have a hunch that it would smell like Poudre B.

[@kiwiruna9077]

It's good to know that the Chieftain is bit of a Trekkie.

[@pierredecine1936]

haha, quite a mood you were in (in) this one - laughed out loud, I did.

[@russwoodward8251]

Fantastic research. Great documentation. Thanks.

[@dcpack]

Just notice the TOS Enterprise on the desk. Class.

[@captdavid160]

Always a pleasure to listen to the Chieftain while on lunch break drinking a cup of joe

[@hashteraksgage3281]

I know the answer, but... Joe?

[@HMSVanguard46]

@@hashteraksgage3281 JOE MAMA!!

[@bluefletcher4340]

Or a beer.

[@abzzeus]

One effect the 17 pr that you haven't mentioned is on morale. British crew knew if Gerry comes along with his Tiger (Americans fought no Tigers vs tank battles in France just the 3 wrecked ones on the railway cars) they could call on the firefly and that could destroy Gerry. likewise on the German side, if you're fighting a group of Shermans and one suddenly fires what is a massive blast and the tank next to you that has been bouncing off the normal shell, just blows up you realise that something out there can kill you, so you're a bit more cautious

[@attilarischt2851]

How many microphones have you gone through the last year, considering we just saw you mourn another one?

[@TheChieftainsHatch]

Four, I thiink. I killed another one when I was re-recording for the other broken one. I lost at least one at Rock Island, and I suspect there was another somewhere which I can't place

[@shinybaldy]

chris younts not really. Studio sound recording is typically done with a boom with a shotgun or condenser mic. Chieftain’s simple lav mic setup works and killing lav mics is just part of the process - cest la vie.

[@turbowolf302]

@@TheChieftainsHatch one a quarter seems to be an alright mean service life, seeing you've been allover the world.

[@shinybaldy]

chris younts that’s usually the news.

[@southronjr1570]

As a student of ballistics (internal,inside the barrel, external, outside the barrel but before on target, and terminal, what it does on impact) I have a theory why the 17 pdr had so many issues. When designing a barrel the engineers have to find a compromise in the projectiles and powder charges to design the rifling, twist rate, and barrel length to. It even gets down to the particular shape and finish on the rifling to gain the most accuracy. If the original designers didn't have the sabot ammo to design for, or if other factors like what the gun would MOST commonly use, then they couldn't take the oddball shells into account. For a similar gun with a similar problem, look no further than the M16'w early problems in Vietnam of US soldiers being found with guns broken down and had died while trying to clear the broken shell out of their weapon. In that case, the designer based the barrel and gas system off one particular bullet, powder, and case combination and the newfangled ball powders came out with faster burn rates and an egotistical sob overruled the ordnance board who didn't want to use the new powder with the new gun and it was sent over anyhow. Thus the M16/AR family of guns were demonized early on in their use because of such massive failures and the guns being so inaccurate initially. To give you an idea, the bullets were so unstable with the as issued combination, the bullets would begin tumbling on their own at around 300 yards, that's if hey didn't get hit with a cross wind or small debris like a leaf.

[@ditzydoo4378]

YES! Thank you for putting this point of contention on the 17-pounder to rest... I love your analysis in the video of D-Day in saying the reason Firefly has it reputation in that instance is that the British brought them and the American commanders at the time saw no need in switching to the 200 available 76mm Easy-6 tanks stuck in England at the time of the invasion... Oops! (your phrasing). Hoping you have a stellar new year, and I look forward to the next chat. cheers... ~_^

[@DC9622]

DitzyDoo go find the US Army Armaments Research and Development report January 2018 on the performance of 76mm M1 gun. It is on line. This use modern technology to test the performance. The conclusion to paraphrase The British understood the issue and produced the most effective allied anti tank gun of the war, the 17 pounder long barrel gun. Basically their testing agreed with the Normandy 1944 field testing and Eisenhower’s summery at the time.

[@tyler2259]

DC The 17pdr was found to be superior in terms of penetration to the 76mm mounted in the later version of Sherman tanks, people knew that even during the war, but US Army ordnance in their testing found the 90mm Anti Tank gun, superior in accuracy and penetration to the 17pdr, hence the US never bothered with the gun as the difference between the 17pdr and the 76 wasn’t large enough to make a difference in the majority of armored engagements

[@DC9622]

Phantom Taurus go read the US Army 2018 January report, by the Ammunition Research and Development. They disagree.

[@DC9622]

Phantom Taurus apps.dtic.mil is the site, google AD-E403 980, the full text should be available.

[@ditzydoo4378]

@@tyler2259 the Chieftain did a Q&A called Myths of American Armor. TankFest Northwest 2015, were in one of the topic's he talked about was this subject. Here is the link: kzbin.info/www/bejne/mH_NoZJqn75rprs

[@heimvar]

Man I'm happy KZbin's algorithm showed me your channel. I like your content and opinions a lot. Keep going on nan

[@cyberstormalpha789]

I love how you have the "NCC 1701, no bloody A, B, C, or D" on your desk.

[@ataxpayer723]

That is the ACTUAL NCC 1701. The entire StarTrek Universe is populated by very very small people. Thats why the "starships" can move from one star system to another. They are all contained inside one guys home office.

[@Peter-lm3ic]

When I first joined as an infantryman in the British Army in 1950 the Battalion had 6 x 6pdr Anti tank guns pulled by the Universal Carrier. At this time the 17pdr Anti Tank was only in Royal Artillery Regiments pulled by the US Half Track. In 1951 our 6 pdrs were replaced with the 17 pdr pulled by the Oxford Carrier an up rated version of the Universal Carrier. The RA A/T Regiments were disbanded. The 6 pdr was much liked by all particularly the old soldiers who had used them with great success in the Western Desert against the Germans and Italians. Funny enough they also had respect for the previous 2pdr A/T gun considered quite a useful weapon against vehicles. The 17pdr was in comparison to the 6pdr was big and took some handling when positioning, but at the time there were few weapons about that had it's equal. At about that time our PIAT anti tank weapons were replaced as a temporary measure with the Energa rifle anti tank weapon which the launcher was carried by all. The PIAT also had respect as it could be fired under cover in buildings and slit trench's without blowback and was issued one per platoon by a big lad as it was quite heavy! Happy days!

[@joeblow9657]

I didn't know I needed a video on the 17-pounder's accuracy until Chietain uploaded it.

[@ABrit-bt6ce]

iirc 17pdr inaccuracy is filed alongside headspace and rimlock.

[@jic1]

@@ABrit-bt6ce Not for the sabot rounds.

[@SlavicCelery]

@@ABrit-bt6ce unfortunately the ergo facts still remain the same.

[@DC9622]

Joe Blow go on line look for US Army Ammunition Research and Development report on 76mm M1 gun. January 2018. They tested the performance using the modern methods employed by the US Army. To paraphrase part of the conclusion the British produced the most effective allied Anti Tank long barrel gun in the 17 pounder. The objective of the exercise is to penetrate the armour. The report agrees with Eisenhower’s opinion of June 1944. Perhaps the best statement is attributed to Alfred Rubbel, “Sherman’s we laugh at them, unless it’s a Firefly”

[@kidmohair8151]

ex audio guy here.. for the sit down at a desk stuff, get yerself a good ole regular plug-in mic, and put it on a desk stand... they are comparatively bullet proof and a decent one will put you back a C-note or so, and with an adapter you can even plug it into your radio transmitter... the only time that lapel mics need to be used is when mobility is desired

[@johnnyzippo7109]

I always enjoy kickin back with a frosty carbonated “apple juice” watching some Chieftain aka The Tank Professor talkin guns , gears and gear.

[@leoschorberschofskie4628]

Well, I guess it's more accurate then the camera focus XD But for real, nice video! Content over visuales.

[@SHcinema]

I guess that points out a good reason why a smoothbore with fin-stabilized ammo is now a common sabot round. We're back to launching arrows at each other! LOL!

[@allegrofantasy]

Excellent presentation- not a wasted word. Well.....maybe just one.

[@frontiersmandavis1857]

Enjoyable & informative, thanks. Now a new question, what was the first tank to use track pads and the story behind it. Keep em’ coming!

[@JustSomeCanuck]

Well, I know of one account from Canadians near Juno Beach. A Sherman Firefly destroyed/disabled five attacking Panthers with five shots. I'm guessing that wasn't with SVDS rounds, so this certainly demonstrates the 17 pdr with APCBC rounds worked just fine.

[@ToddSauve]

That sounds like that battle near Bretteville where some 1 Hussars Fireflies caught seven Panthers with their sides facing them, due to wanting to keep their frontal armour facing the anti-tank guns they were attacking. One guy nailed five of the Panthers from 1000 yards! So obviously the 17 pounder was sufficiently accurate at even a kilometer's distance.

[@MultiZirkon]

09:00 "...a matter of condension..." :-) -- Ah not only Bismarck, but now also The Chieftain forces us to keep our ears open to not loose delightful small nuggets of verbal prose :-) (y)

[@stevefreeland9255]

Next Chieftain video should be called “The HE u give!”

[@dr.ryttmastarecctm6595]

Thank you for the always informative upload.

[@5RndsFFE]

Love the second shirt mate, hope the weather in puckapunyal was kind to you haha

[@kellybreen5526]

Continuity error at 7;00. New shirt! Interesting video.

[@andrewcoley6410]

As always facinating and entertaining!

[@douggallagher8809]

Huh, this puts into perspective of all the towed A/T guns put into tank roles & how the deficits begun or maybe carry over. Adding into the military's perchant for just saying "good enough". But new question: the 17pr, 76mm, pak40 75mm, pak43 88mm all started in a towed A/T mount before being pressed into(quite literally) the tank roll. What was there cumulative accuracy compared from the towed mounts to their respective tank mounts? We have the US figures for the 76mm & 90mm but what of the german stuff?

[@corymcgrath5652]

My Grandfather was an artillery guy during WWII, 23rd anti tank RCA, attached to the Canadian second Div. He was in charge of a self propelled that was a 17 pounder. I asked him how many tanks he shot up. He replied, never seen an enemy tank, shot it at everything else but.

[@PeterMultyGaming]

why i'm always laughing my ass off in your serious videos? excellent explanation!!

[@BillHalliwell]

G'day Nicholas, Being an air force type, the finer detail of tank ordinance is still somewhat of a mystery, yet always interesting. Whenever my ignorance began to glaze one's eyes, I pondered your tiny model of NCC-1701. Now, that's some ordinance I really would like explained to me. What warms one's heart is to find, like me, another 'grey-haired' gentleman who is a Star Trek fan. As the late Mr Roddenberry was a brother air force type, from the very first series I was fascinated with his worldview of the future. His Enterprise(s) were always stated as ships of peaceful exploration yet they all carried a vastly powerful array of futuristic weaponry. His world was one that didn't need money, had total gender and race equality, respect for any type of life-form and, as Captain Picard once said to an Earthling from the past, "...our motivation is for the betterment of humankind...". Still, they were armed to the gills for, firstly the Klingons and later the Romulans plus those pesky, chuckle-heads, the Borg. Finally, to the point: even in the 24th Century and beyond there will always be a need for someone like your good self to explain the intricacies of the weapons of war. I may not understand all of what you say, Sir Nick, but I do like the way that you "make it so". Cheers, BH

[@z_actual]

update, prior to previous discussion have acquired some RAN antiflash for trialling with civil fire service, mostly because we could get that in a day thanks for your help on this matter

[@TheChieftainsHatch]

Huh. Who did you go through, as a matter of curiousity?

[@Sim.Crawford]

@@TheChieftainsHatch At the moment you could just raid a locker on Choules or Adelaide (we're a bit on fire at the moment).

[@z_actual]

@@TheChieftainsHatch Discussions got the ear of a now deployed RAN reservist officer who is in a sister unit nearby and he seems to think he can facilitate hoods which come with gloves in bags worn by the user. He's talking three, one of which we have already have which is enough to evaluate the usefulness. Equipment for these firemen such that it is, is pretty poor and well due for an upgrade and they hope to be in a position to pressure the state and fed govts where there's expected to be an appetite to throw some money at them. This group lost 2 trucks and all their gear, the thinking is that at least they can ask for the replacement trucks to come with with anti-flash kit as its a small percentage of the unit cost. Not to get too far in front of ourselves as first it has to get through evaluation, but basically thats the plan. Theres lots of analysis going to take place over the next little while including providing monies for the volunteer fire fighters (who basically get nothing) and equipment like fire fighting aircraft which is bound to be expensive, so the Fed are aware theyre going to have to let go of a bunch of money. This outside of roads, signage, post offices and things that have been totally lost.

[@z_actual]

@@Sim.Crawford I think thats pretty close to whats going on as the HMAS Adelaide was deployed a few days ago. Theyve been pulling up Army reservists, medicos and veterinaries at the same time, but like you say people are pretty busy both sides and Kangaroo Is isnt a settled thing yet and some resources are still needed locally.

[@Sim.Crawford]

@@z_actual guess who isn't RAEME on fire duty due to a fucked L5. I know how it goes.

[@mathewkelly9968]

The 17 PDR in the Achilles is what everyone forgets about , the Brits had regiments of them .

[@KevinSmith-ys3mh]

Agreed, probably the better option to go for would have been to attach an M10/M36/Achilles to standard tank platoons (boost size to 5-6 tracks each) and perform it's Tank destroyer missions as designed, a long range puncher to engage and pin the opposing tanks while the rest of platoon maneuver for flanking shots and close to their effective ranges. I suspect the open more spacious turrets of TD's enabled much better use of the 17pr gun at that time.

[@SvenTviking]

I was told that the problem with Sabot ammo on the 17 pounder was there were two manufacturers, one who made them correctly and one who didn’t. Noe if the correct manufacturer was solely the supplier of 77mm ammo for Comet, with it’s slightly smaller shell case, then all the 77mm would be accurate.

[@flakpanzer_gepard]

The issue with 17pdr APDS inaccuracy is well known. Besides The Chieftain has said something about Canadian shells for the British guns, but I cannot find anything about it, however I know that some reports exist

[@demosthenessirony4774]

I believe the term alibi is in connection to airborne operations (alibi pass has always referred to when a bird isn’t able to drop its full chalk in one pass) and some how found its way into daily hub meetings that battalions have in the morning and so on. But this is just my personal observation and theory

[@dermotrooney9584]

Balanced, considered and informed. This is not suitable for KZbin but please keep it up. ✊

[@texasdeeslinglead2401]

Really enjoyed seeing you and Ian chatting . Now for the most interesting personalities for these topics , you have to convince Bob to get in front of camera with you . Say maybe on the topic of reviving all of these beauties we talk about .

[@siem3113]

Some accuracy tests from '45 would be nice as the APDS ammunition was updated between the start and end of the war we know that, but given the info at hand I agree.

[@TheChieftainsHatch]

So many say, but even Shot Mk 2 seems to be a post-war development as best I can find. And whatever the improvement, it still was considered worth issuing an accuracy improvement in the 1950s, so whatever the accuracy improvement may have been, it seems not to have been particularly good.

[@siem3113]

​@@TheChieftainsHatch Going off of the Challenger A30 May 1945 manual I have the APDS is listed as Shot A.P.D.S Mk. I . B . T. I don't know what the difference between Mk I A and Mk I B is but it does show there was some sort of a change, if you have any info on this would nice, other sources I've seen simply refer to rounds as APDS/T, Mk I APDS or Sabot Wt. It does still allude to the inaccuracy of the round (perhaps to a slightly lessened degree), as it says: RANGE (extreme effective) APDS - 800 yards. AP - 2,500 yards.

[@TheChieftainsHatch]

@@siem3113 Interesting, but the next question is if Shot Mk IB was the production batch by May, and the US testing was delayed until Aug 45 due to delivery of ammunition, which version would have been shipped over? Unfortunately, the US test report does not say. I'll see if I can find a blow-up of the photo of the round I used in the thumbnail.

[@siem3113]

@@TheChieftainsHatch Sure, heres a pic if that helps at all. imgur.com/go1m5vN It can't be that much more accurate but I'm curious as to what the change was. The manual also states 20% APDS, 30% APCBC, 45% HE and 5% smoke so it was getting pretty common by the end of the war. Ofc we can't verify thats accurate to what was around at the time but it says (when available) next to the smoke but not next to the APDS suggesting theres not much of a supply issue. Also interestingly one of the HE rounds in the 17 Pounder seems to have about 33% more filler than the 76s own HE shell which is confusing as I thought the 17 Pounders HE was very poor. If you have any thoughts on these I'd be glad to hear them. Sorry for going off on a tangent about this but it's the only manual source I have on anything and it's been helpful with some non tank historical info as well. If you know of any other manuals documented online (for other tanks or equipment (prefererably western) I'd be glad to have a link. Can't afford to order any atm, but I got the book Troop leader for christmas so thats nice too, apparently they were issued tabby night vision devices (or a device) by the time they were issued M24s so I look foward to getting to that bit of the book. Edit: He also refers to some Stuart tanks as honey's in the book.

[@richpurslow3283]

We needed a gun that could deal with any heavy armour reliably and the firefly did just that. Absolutley tons of accounts to that effect. Loads of panthers falling to them and aparently whittmans tiger counted amoung the dead too. Was it ideal...not exactly. Was it in service before the end of the war..yes. It was what we had and did the job.If i had to face even a late mark panzer 4 or worse id feel better knowing the gun we were using could stick a round through it nicely.

[@christineshotton824]

For a cobbled together expedient of a towed anti-tank gun and a tank turret never designed for such ordnance, the Firefly was an amazingly effective package. It's enough to make me believe that the UK also possesses innovative hillbillies with welders, as does the USA.

[@sarahshaw7315]

@@christineshotton824the British are the definition of ‘innovative’… everything they do is boarder-line Wallace and grommet inventions. Rather than building something around the idea they build the idea around the something. We want a tank that can counter tanks Shove this one in literally every tank we have! We need a fast tank Shove this engine in about 10 different designs , one of them is bound to work Our cromwells are not doing as well anymore Stick this plane engine in that sucker and go from there!

[@trooperdgb9722]

That applies to the Sherman itself. Was it great? No. Was it good enough? Yes, especially as it could be built in overwhelming numbers.

[@carebear8762]

"Alibi" is a Rifle Marksmanship term, refers to an "alibi round". As a Marine NCO I would reference MCRP 3-10, Appendix A. Training, Pg A-8 Alibis . "An alibi will be awarded during qualification firing if any condition caused by the weapon (i.e., mechanical malfunction), ammunition, or range operation, either line or pit, causes the Marine to not have an equal opportunity to complete a string of fire. An alibi will not be awarded for any condition caused by the Marine." Used colloquially when instructing or briefing for covering something inadvertently left out. Which frequently, to be precise, is a result of "briefer error" and thus would not qualify as an "alibi round" on the range.

[@colbeausabre8842]

"Alibi firers, watch your lanes!"

[@Kman31ca]

That's still more than accurate for tanks as targets.

[@randymagnum143]

If you dont mind getting really close to them.

[@901Sherman]

@@randymagnum143 Still far from 'point blank' by tank combat standards

[@bongobrandy6297]

It appears that the choice of shirt dooms a microphone to death in public. Choose wisely Chieftan!

[@rover213]

question... jj abrams star trek or original star trek movies?

[@fabiogalletti8616]

Look "no bloody A, B, C or D", I guess.

[@markwilliams2620]

TOS. The nacelles shape and their mounting spars give it away. Can't read the upper saucer to discern the ship. It's not being swallowed by a giant space turd so that rules out Constellation. If it's the Valiant it really needs to be treated as a war grave.....though I'm not sure Vulcans have those.

[@ARCNA442]

Does anyone actually like JJ Trek?

[@mbr5742]

@@fabiogalletti8616 m.kzbin.info/www/bejne/jpC0YXuYmZWtbrM

[@janetrickwood2484]

I love the idgy-bidgy Enterprise between the tanks, Chief. Vulla!

[@lkchild]

ace video, this answered a lot of queries - thanks!

[@LikeUntoBuddha]

I'm a little confused over the 17-pounder vs the 76mm. Were there two of them? Which one is the one that went on the Firefly? Is that one different from the 76mm we used? Were they both rifled or not? I love the way we Americans go for data and the way we break down our own war experiences. I remember that due to Civil War journals, Europeans thought the Americans were "weak" but really, we were honest and did not write about everything is great and rosy.

[@johnknapp952]

17pdr went in Sherman Firefly which is a different gun than the 76mm which went into Shermans. Another way to look at it, one is British and one is American.

[@jic1]

If you want to get even more confused, the American 3", 75mm, and 76mm guns (and the British 17-pounder) all had the exact same bore diameter.

[@DC9622]

LikeUnto Buddha the Germans had the same problem. They captured a Firefly, and initially referred it to the Sherman 76mm, Weston T34, which they encountered on the Eastern front. They released it was the British 17 pounder after testing. The 17 pounder round was significantly heavier hence it’s better penetration. Another interesting fact is the Firefly Sherman has the lowest lost rate, and less likely to brew up,possible because the rounds required the storage to be redesigned.

[@vicpecka7356]

Are you sure of that? The QF 17-Pr, 76 mm Gun M1 & 2" Gun M7 all had a bore diameter of 76.2 mm while the 75 mm Gun M2/M3 had a bore diameter of 75 mm.

[@LikeUntoBuddha]

So...which was better or was it a situation like the British wanted "their gun" which I do understand. For so many reasons it is better to cut down the kinds of shells you have to carry. I think the British liked their guns even though a lot of them had no or a small HE round. I still think the Jumbo Sherman was the "Infantry tank" that the British wanted but for what they wanted it for (Replacing the Matilda and the Churchill) it seems like our 75mm would be the best gun. It has a "decent" anti-armor round but a great HE one. I do find it very interesting that the famous "76mm" we read so much about it not very accurate. I thought most British guns were.

[@Tomartyr]

To put these into context both the 17pdr and 76mm were shooting well below 1 MOA which is the accepted starting point of precision or 'sniper' rifles, both are very very accurate.

[@AKUJIVALDO]

Tell that to 17pounder APDS LOL

[@jacktattis]

@@AKUJIVALDO 08 Aug 44 1NY Trooper Crittenden Firefly No 4 2 x Panzers 1650m Source S A Hart Firefly V Tiger Normandy 1944 Page 64 Round of choice APDS

[@henrynelson11]

Good video! Any chance on a closer look on the Challenger's mounting of the 17pdr to compare with your analysis of Firefly?

[@baby33341]

How did other Anti Tank Guns from countries such as Germany, Japan, Italy compare to the UK, US? Any documents links?

[@stuglife5514]

baby33341 PaK 40 intensifies

[@simonh317]

So why the legend of the Firefly? The British had them on DDay and for the Normandy Breakout - the US Army did not have the 76mm......

[@Caratacus1]

The legend starts because all the Tigers and Panthers in France were sent to fight against the British and the 17pdr saw them all off. It didn't matter that the US only had 75mms because they were facing infantry and a few knackered old French or German medium tanks. By Mortain Allied air-power had wrecked any hope of a German success.

[@fcp5039]

My question is: can APFSDS(T) ammo penetrate the shielding on a Constitution class?

[@OmegaReaver]

Original or refit?

[@kmckay7086]

Always entertaining and informative

[@Jawzzy]

How does the accuracy of this guns, installed in the Sherman, with ww2 ammo, compare to the KWK42 installed in the Panther?

[@catlee8064]

Could you make a video about the smoothbore cannon into the CR2, CLEP. And the expense/costs/logistics of it ?

[@fenixmarcus10]

will there ever be a t-72 review, switchology and fire control? as always love your videos. take care.

[@TheChieftainsHatch]

Yes, and yes.

[@fenixmarcus10]

@@TheChieftainsHatch thank you for answering my question. i appreciate it.

[@Duke_of_Petchington]

I have to Ask Nicholas, would that later model Sherman turret made for the M1/M1A1/M1A2 76mm Gun, been a some what better fitting for 17 PDR gun? I ask this out of curiosity, and I under stand it still would’ve had to modify it slightly like the OG turret model.

[@ihategooglealot3741]

Possibly but the US decided to go with their own high performance 3" gun and neither the UK nor US wanted to have the difficulty of supplying both - then by the time the later turrets were available in numbers the war was coming to an end and the UK only wanted Comets and then Centurions (the vastly larger Centurion turret ring made it a much nicer place to use a heavy gun than sherman was ever going to be).

[@Duke_of_Petchington]

Ihategoogle Alot it’s one of those thing that never got tried out.

[@ihategooglealot3741]

Yes, that's the case according to the information I have available, certainly I can't imagine that by the time the allies were up for messing around the whole British effort was focused on Centurion.

[@Duke_of_Petchington]

Ihategoogle Alot Centurion And Black Prince

[@hammer1349]

I believe the word you may be looking for is addendum, meaning that additional information added after printing etc so in this case filming or going through the script

[@ataxpayer723]

My dog ate my addendum.

[@southronjr1570]

As a student of ballistics (internal,inside the barrel, external, outside the barrel but before on target, and terminal, what it does on impact) I have a theory why the 17 pdr had so many issues. When designing a barrel the engineers have to find a compromise in the projectiles and powder charges to design the rifling, twist rate, and barrel length to. It even gets down to the particular shape and finish on the rifling to gain the most accuracy. If the original designers didn't have the sabot ammo to design for, or if other factors like what the gun would MOST commonly use, then they couldn't take the oddball shells into account. For a similar gun with a similar problem, look no further than the M16'w early problems in Vietnam of US soldiers being found with guns broken down and had died while trying to clear the broken shell out of their weapon. In that case, the designer based the barrel and gas system off one particular bullet, powder, and case combination and the newfangled ball powders came out with faster burn rates and an egotistical sob overruled the ordnance board who didn't want to use the new powder with the new gun and it was sent over anyhow. Thus the M16/AR family of guns were demonized early on in their use because of such massive failures and the guns being so inaccurate initially. To give you an idea, the bullets were so unstable with the as issued combination, the bullets would begin tumbling on their own at around 300 yards, that's if hey didn't get hit with a cross wind or small debris like a leaf.

[@AtlantiansGaming]

I love the little Micro-Machines TOS Enterprise!

[@WildBillCox13]

Curious about ultra high velocity causing excessive barrel wear and, thus, affecting gun life. 17pdr was thick and heavy; was that in part compensation for the extra heat? Did 17pdr have the same ( 900 round) life before replacement or resleeving as most guns?

[@randymagnum143]

Throat erosion is what does a barrel in, and if you were shooting sabot, it would probably be as short as a few hundred round.

[@mdtdragon]

Did the Archer and Achillies show the same problem as the Firefly?

[@Caratacus1]

Not sure about Achilles but Archer went on to have a significant post war career and was liked by its crews. So I would guess that there were less issues with its 17pdr or it would have been phased out quickly.

[@Soleil_de_Helturel]

the standard AP was serviceable (great penetration despite the mediocre accuracy) and worked well on tank destroyer platforms. It was less effective on the firefly because the tank wasn't built for the gun. Also tanks tend to shoot at more targets than just other tanks meaning you need other effective shell types beyond your AP shell. Between the great penetration of the base AP shell and a platform designed to support the gun properly, the 17pdr stuck around on those other platforms a lot longer than the firefly.

[@wyverncoch4430]

Also wondering about A30 Challenger, which had a turret built to except a 17 Pdr. Too big to be practical, which was why the firefly was developed but was still a workable solution

[@greva2904]

Wyvern Coch Not so sure about the A30 Challenger being too big to be practical: it’s actually not quite as tall as a Sherman - it just LOOKS really big in illustrations due to the turret looking out of proportion in relation to the hull. It’s actually a bit of an optical illusion.

[@melvillesperryn9268]

@@wyverncoch4430 I think the problem was that the Challenger turret had to be big enough for 2 loaders per design requirements

[@Paul-ie1xp]

British Ammunition production was infamously iffy... I wonder if that didn't influence the large group size.

[@brianmacadam4793]

We've had an explanation of accuracy of the rounds, my question is: during WW2 how far away would tanks actually fire at each other? Would tanks recognize targets at a distance (what distance) or was it typical to set up in a good spot and wait for the enemy. How hard was it to see the enemy, stop, take aim and fire?

[@colbeausabre8842]

IIRC, The US Army's post-war study said 800 yards (about 0.5 mile) was average engagement range

[@lyndoncmp5751]

@@colbeausabre8842 Yes, that was the mean range, although it varied from under 100 yards to nearly 3,000 yards.

[@jrd33]

Very much depends on the terrain. In Western Europe, visibility is very limited and tanks often fought at a few hundred yards. On the Eastern front, tank duels at over 2,000 yards were frequently possible. Most gunners will fire as soon as they can, or possibly as soon as they think they have been seen if they are in ambush. Even if you don't think your rounds can penetrate, you might get a lucky hit or cause the enemy crew to panic.

[@DC9622]

Interesting, the analysis by Mark Hayward The Sherman Firefly 2001, has a slightly different conclusions worth a read, but to be fair, this subject has always resulted in agreeing to disagree either side of the pond. He interviewed, the guys who used firefly in anger, who to quote, didn’t have a problem with it. So it is the old problem, it’s all down to the crew, or if you got something potentially firing back at you, then you are more focused. Indeed during Normandy they used APCBC, the APDS arrived late August. The British firing instructions for Comet indicate APDS 1200 yards against German armour, though I am not aware of its use, although comet did successfully engage Tigers. We know from the No2 ORS analysis, that the British view, is fit a bigger gun, than bolt on extra armour to a Sherman, so Firefly approach not Jumbo. We also know that the 17 and 6 pounders had high performance for penetration in combat particularly the 6 pounder above 90% but the 3” M10, was only 77% (this includes Mark IV, so less when fighting the cats) and the 75mm 38% when fighting the Tiger and Panther. Mark Hayward, covers this in detailing which includes the 76mm, which has inferior penetration capabilities. Also their analysis determined the combat was an average of 405 yards closed country Bocage whilst 1204 yards open country once they had broken out. However, the success range for 75mm tanks, was 580yards and the 17pounders Firefly and Achilles was 1100 yards against all German tanks. So the 17 pounder tanks successfully range is nearly twice that of the 75mm tanks and consistent with the German tank ranges. It should be noted at this point 14% of tank actions were tank on tank, the majority were against machine gun, towed and SP anti tank, hence the importance of the 75mm tanks which has the best HE round. It should be remembered when the 76mm tanks were received, they still had Firefly’s to babysit. British didn’t rate either 76mm or the 90mm possibly because the 20 pounder was in development. Best tank, is the 75mm Tank, with Firefly to babysit until Comet and ultimately Centurion, by which time they sorted the HE round.

[@SlavicCelery]

Not to mention most of the tank on tank combat in the Western front took place at relatively close range (Africa campaign not withstanding)

[@DC9622]

Timothy Soen indeed typically 400 to 480 yards according to the combat analysis of the time. The 17 pounder tanks, firefly, challenger and Achilles tended to be in overwatch, at the back of the troop. The famous August 8th engagement, the Firefly was under instruction from the Squadron commander, holding its fire until 800 yards, so the 75mm Sherman’s could engage with HE, forcing the Tiger crews to close down, thereby limiting vision. Then the Firefly engaged, the rest has they say is history, they worked has a team not in isolation. Another engagement was by the Staffordshire Yeomanry on D Day, against 21st Panzer. The Firefly’s engaged the Mark IV’s at range, very one sided.

[@SlavicCelery]

@@DC9622 Surprisingly is it's almost as if combat is multifaceted with a number of arms supporting each other. Not just a series of statistics for machines.

[@DC9622]

Timothy Soen indeed combined arms, they fight has a team, the armour, infantry and artillery with tactical air support. 21st Army had 79 Armour with the funny’s which could overcome any obstacle. The Crocodile Adder and Conga were terrifying things, for breakthrough with the AVRE.

[@CMDRFandragon]

Whats the penetration for the 17lber? Does WoT get it even close?

[@Jasontvnd9]

It's actually pretty close , In tests the APDS would go through 241mm at 500 yards.

[@matthiuskoenig3378]

@@Jasontvnd9 and its APCBC?

[@Jasontvnd9]

@@matthiuskoenig3378 according to data 175mm at 100m so 171mm at point blank in game seems a little conservative. On looking into it further tests show the APDS would penetrate 275mm at 100m so in theory it would be able to go through the front of the experimental Maus tank. Alot is said about the innacuracy of the APDS rounds at longer range but in the real world the standard APCBC would penetrate everything it met on the battlefield from almost any range.

[@tellyknessis6229]

As a linguist (from the naval environment), I'm interested in the pronunciation of "sabot". Seen it English print media, but never vocalised. I had assumed (to use an AFV friendly term) "s + Abbot" for rough, tough anglo-saxons. Originally, a french word for shoe/clog, so logically it should be a short/hard "a" rather than long/soft, right? Similarly, a silent "t" - or was that lost on the tankies/gunners? (It's where sabotage came from - the Luddites sued to chuck footwear into the powered weaving looms to wreck them.)

[@TheChieftainsHatch]

You are not wrong. The American pronunciation as "say-bow", which I use in my videos, is, in fact, incorrect. I have heard the 't' pronounced in some places, but not commonly.

[@johnward8995]

It's originally a French word so ideally "sabbo"

[@alexbowman7582]

The German famous 88mm was said to be 100% accurate at 1,000 metres although in battle conditions it was probably less accurate.

[@TheChieftainsHatch]

Very much so. 10-20 shots per kill was about normal in North Africa and the Eastern Front. See "Dreaded threat: The 8.8cm in the anti-tank role" by in the Panzer Tracts series.

[@MagpieOz]

"I hope I don't need to come back to this again" ...... LOL, you will need to I'm sure

[@PrivateMemo]

What does SVDS stand for? Never heard that abbreviation before

[@Sakkehattu]

Super Velocity, Discarding Sabot. It's the same thing as APDS, just alternative / older name for it.

[@PrivateMemo]

Sweet, thanks man.

[@DocSeal]

Quick question, what does SVDS stand for? I'm assuming the DS is Discarding Sabot, but I'm having trouble figuring out what the SV stands for. It sounds like it's just a different name for APDS, but I could be wrong. Edit: After some googling and inferring from the HVAP abbreviation, VDS is probably Velocity Discarding Sabot, but I'm still not sure what the S is. Supersonic is, well, technically not wrong, but it's a hell of a lot faster than supersonic so it seems a bit pointless to call it that.

[@SlavicCelery]

Standard velocity discarding sabot. Apposed to high velocity discarding sabot.

[@TheChieftainsHatch]

Super velocity discarding sabot.

[@DocSeal]

@@TheChieftainsHatch Thanks!

[@VhenRaTheRaptor]

@@DocSeal You see some similar differences in terminology for the British IIRC.

[@SvenTviking]

From what I’ve read the problem with Sabot was that there were two manufacturers, one who worked out how to make the round accurate and work, and one who didn’t. Now interestingly, the Comet Sabot was considered more accurate, but the projectile is exactly the same as the 17 pounder, the only difference being the size of the shell casing and thus the quantity of propellant. Was the “77mm” Sabot ammunition for the Comet gun supplied by the manufacturer who made the more accurate ammo?

[@BA-gn3qb]

Was the 17 pdr accuracy problem only in the firefly? I would think so. Considering the Sherman tank's high profile and suspension was made for a lower velocity gun. The 17 pdr would "rock" the tank more when fired. Thus reducing accuracy.

[@501Mobius]

@ B.A. The Mk I AT gun on a Mk I carriage was less accurate. The AP and APC was less accurate than the APCBC shell. But, the 10 shot test shown was just one of a number of tests that were about the same for the tank gun and AT gun.

[@31terikennedy]

The Brits went with the 17pr for the simple reason that it was in their logistic tale.

[@dustinhall637]

why did they not put a 17pd in a 76 sherman Turret?

[@TheChieftainsHatch]

Didn't seem to fit well, apparently. It would seem the trunnions were too far forward.

[@matthiuskoenig3378]

@@TheChieftainsHatch why did they not design a new turret for it? the Ausies did it for their 17pdr in the AC4 prototype. or even use the ausie's turret? they could make tanks for themselves, and they got the americans to do a special turret for the grant, so why not a turret fro the 17pdr?

[@nickbrough8335]

Hi there. Was the only difference between the 17 pounder on the Comet and the Firefly the length of the barrel ? Would the Comet 17 pounder have been a better choice for the Firefly (had it been available in 1943/4) ?

[@TheChieftainsHatch]

Chamber size was different. Breech came from an older gun.

[@nickbrough8335]

@@TheChieftainsHatch Thanks. I think the shells were shorter as well, so it would probably would have worked better in a Sherman turret.

[@CZ350tuner]

The WW2 US HVAP (APCR) round was designated M.93 and was available in versions for the 75mm. L.41, 76mm. L.52 and 90mm. L.52 tank guns. The WW2 90mm. APDS round was designated M.304.

[@Perfusionist01]

Very good information. Your background a a trained armor officer and your experience with physically examining so many tanks gives you a lot of credibility (to me at least). It sure beats the people (usually from Britain) who decry the US Army as idiots for not adopting the Firefly immediately after its initial field trials. while it MIGHT have proved useful in certain situations, it would not have reduced the tank casualties in the bocage as many of the losses were attributable to bad terrain and green units having to "learn under fire". It would have been interesting to see if US Army Ordnance could have addressed the problems of accuracy and could have improved on the HE shells. Unfortunately the new ammo probably would not have been available before 1945 anyway. I appreciate your reminding us that a tank is a SYSTEM, not just a mobile cannon that is assessed by statistics.

[@jic1]

Exactly. The 76mm was more than up to the task, and was left behind for what (without the benefit of hindsight, and maybe even with it) were very good reasons. If the Firefly had been adopted, that would have been left behind too.

[@Caratacus1]

You're right the 17pdr would have been pointless in the US sector of Normandy because there were no heavy tanks like Panthers or Tigers for them to shoot at.

[@neddy4702]

theres a interesting piece of german cruiser? armour at the royal armouries fort nelson near portsmouth that was used as a target for 17pdr guns, accuracy issue aside the penetration on the gun is incredible, from memory the target is at least 100mm thick and the 17 just punched holes right through it.

[@nashuf1492]

Twist rate of the barrel ! The Std heavy (slow) round stays stable at all distances. The Sabo Light (fast) round looses it stability and thus accuracy at distance because its needs to spin faster than can be achieved with the twist rate of the standard barrel, ammo design configuration.

[@Bird_Dog00]

Doesn't explain why different guns of roughly the same bore diameter had wildly different accuracies with the sabout round. Sabout separation does shound like a logical point to start. Muzzle break may have ben an issue. May have ben a "murder in the orient express" szenario (spoiler: more than one culprit).

[@nashuf1492]

@@Bird_Dog00 Orient express could be a factor in all this but however the 77mm and the 17pdr ammo/gun are not the same. Different bore size, velocity and design weight of projectile would change the twist needed to stabilize them.

[@fastmongrel]

@@nashuf1492 The 17 pdr and the 77mm were the exact same bore size 76.2mm. The shells were also the exact same size and weight it was the powder case that was different the 17 pr powder case was 583mm long the 77mm powder case was 420mm long to make it easier to handle in the cramped Comet turret. The 77mm was very accurate still not up to the US 76mm but that was an exceptionally accurate gun

[@nashuf1492]

@@fastmongrel I hope the Chieftain could find out and answer this accuracy problem for a future video. If what you say is correct, i still would think that the twist rate would be different (tighter) in the 77mm as the velocity is slower and would need a faster twist to stabilize the standard round if they are indeed of the same diameter and weight. This could possibly explain why one gun shoots and the other sucks with the Sabo ammo but are both ok with there standard ammo. We need twist rates Mr Chieftain to see if they are both spinning at the same rate as they leave the gun using standard and Sabo rounds. Hope you can help

[@melvillesperryn9268]

Surely this is also a function of the APDS shot design? the higher muzzle velocity would lead to a faster spin rate. Perhaps it was spinning too fast? The shot did seem a bit dumpy, rather than the elongated APFSDS shot of today

[@shanesimpson3455]

I have always wondered about future conflicts with 1st world military forces and attrition rates, considering the cost & complex engineering of anti tank missiles could it possible that anti tank guns could make a return to the battlefield?

[@watcherzero5256]

The correct is pdr, its possibly the abbreviation is similarly being abbreviated to reduce the amount of stencilling required. The lb as an abbreviation of pound comes from the Latin 'Libra Pondo' (Pound Weight) 'lbp' which was itself then shortened over time to 'lb' the Pound sign '£' continues this as its a derivation of the Roman symbol for Libra (An L with a cross line through it).

[@peterfmodel]

This is very interesting, explains a lot.

[@CharlesvanDijk-ir6bl]

APDS in other words for the heavies at point blank range. Useful to prevent a tank on fire.

[@satanihelvetet]

Very interesting! I wish for a video about the development of armour piercing ammo for tank guns and anti tank guns from the beginning to today.

[@captainexpiriment9895]

Hey chieftain.. i have a tank question. Why dont tank manifacturers put concrete armour on top of the regular armour?

[@TheChieftainsHatch]

Doesn’t provide anywhere near as much protection for the same weight as metal.

[@captainexpiriment9895]

@@TheChieftainsHatch doenst concrete help with like HE shells and stuff, mind you all this is coming from a 17 year old tank lover, so if i sound stupid thats the reason :)

[@michaelcampin1464]

I suppose if you can get off 5 rounds against an opponents 2 the accuracy becomes a secondary consideration especially when you have gyroscope stabilised guns compared to unstabalised

[@derrickstorm6976]

The fastest 11 minutes of my life

[@MrTangolizard]

Jussi Raitoniemi that’s what my wife says

[@cgaccount3669]

Sadly I'm not able to be a patreon but I'd be interested to know the difference between a cannon, mortar and howitzer etc. Is it just the angle of the gun mount or is there a real difference?

[@nerd1000ify]

The difference is angle, muzzle velocity and intended role. The 'field gun' or cannon is a direct fire weapon, intended to be aimed like a giant rifle at the gunner's intended target. They have high muzzle velocities (typically more than 600 m/s for a WW2 era design) and are generally most useful for destroying tanks and other hard targets due to their penetrating power, though they may also fire high explosive shells at infantry. A mortar is the extreme opposite case, 'lobbing' a high explosive bomb on a high arc so it falls almost vertically on the target. A mortar will generally fire the projectile at less than 1/3 the speed of a cannon, somewhere in the range of 100-200 m/s, and is most useful for killing infantry who are hiding behind an obstacle like a hill- they are rarely useful against tanks. A howitzer bridges that gap: With a muzzle velocity around 500-600 m/s, they can fire projectiles on high arcs to much longer ranges than mortars (the shell may be falling at a 50-60 degree angle on impact) but are usually also capable of direct fire, albeit with shorter effective range than a dedicated field gun. They are usually used for bombarding infantry over long ranges, but may have some ability to fire anti-tank rounds as well. Tank cannons are usually of the field gun type, but some tanks have historically been fitted with a howitzer or mortar for close range firing at infantry or fortifications.

[@billd.iniowa2263]

Was the 76mm gun in the Sherman developed for exactly that purpose? Or was it, like the 17PDR an anti-tank gun shoved into a Sherman turret?

[@greva2904]

Bill D. in Iowa The US armaments board assured Eisenhower that the 75mm fitted to the Sherman was a war winning weapon capable of easily defeating anything the German’s possessed, including Tiger tanks. Thanks to this assurance, the US standardised on the 75mm and there was no incentive to prioritise development of more powerful guns such as the 76mm. That’s why famously, Eisenhower hit the roof when he discovered after D-Day that the 75mm was practically useless against Panthers and Tigers except at extremely close range. That’s why development of the 76mm was so lackadaisical and they never saw service till it was way too late. The US experts got it completely wrong, and then stubbornly refused to admit that they were wrong. Which cost a lot of men their lives. The British on the other hand knew that the 75mm was not capable of taking on the newest German tanks, and acted accordingly. Hence the 17pdr.

[@sean640307]

@@greva2904 that was partially true. The US actually DID have 76mm equipped M4s available for D-Day, but elected to leave them behind in England, as it was considered an unwelcome complication to logistics. The British, on the other had, had no such issues with logistics as the same 17pdr ammunition would have been on the boats anyway, given the standard towed 17pdr required it. It was probably just as well that the US didn't have to face the same German armour in and around St Lo than was encountered in and around Caen.....

[@melvillesperryn9268]

It was a 76 mm at gun with a shorter barrel and lower muzzle velocity.