12.5" is the Bastard Sword of ARs

Watch this video before you run out and build a half-baked 12.5" AR.
12.5" may be the sweet spot of length and velocity, but tuning the 12.5" gas systems for running suppressed/unsuppressed is more difficult than it is with more well established barrel lengths. Is carbine or mid-length better? Not really.
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[@InfernoPhilM]

I’m just here for the reassurance that length doesn’t matter that much. Right guys? Right?

[@VincitOmniaVeritas7]

Right. Caliber is all that matters. Run a .458 SOCOM and everybody will now you are not overcompensating.

[@enmanueldelgado1348]

Lol

[@jmmartin7766]

Unless you use a muzzle break for a 5.56-- THEN you very well may be over compensating

[@shannon3931]

Tempo, mindset and accuracy are foremost, but it does give you more reach

[@sullimd]

That’s what I’ve been told my whole life.

[@TheOfficialCaseMade]

After spending two weeks debating between 10.5" and 11.5" pistol lengths, I just came to the realization that they will both create damn near equal sized holes in the ground when mag dumping at 15 feet away.

[@tommythetrain4288]

LOL

[@johnL-xk2js]

Yep, but equipment wear is an issue also 12.5 patrol length gives a little better gas blow back, when surpressed ...... buy once......

[@gonzob9609]

Dwell time on the 11.5 makes a difference over the 10.5.

[@johnL-xk2js]

@@gonzob9609 yes!! and 12.5 has almost the same balistics as 11.5. I went with that there new fanbled Roscoe 12.5 patrol length system and low and behold works as advertized!! It s worth the extra inch for the patrol system.

[@gonzob9609]

@@johnL-xk2js So the gas length is in between a carbine, and Mid? 11.5 is near perfect dwell time, and the Commando just looks cool! LOL

[@blodus4521]

After spending months obsessing over sbr barrel lengths, 16" sounds pretty appealing.

[@M81_WOODLAND]

At least you won't be over here with us pistol brace peeps wondering what the AFT is going to pull out of their ass in the next week.

[@kerbalairforce8802]

First person to take the ATF to court arguing that if pistol brace=SBR then SBR=common use is a winner

[@jtlegionnaire6310]

14.5 + pin and weld. Still a legal length but as short as possible

[@ReverendMeat51]

Anything shorter than 16" is only worthwhile if you're suppressing it.

[@CaffeineAndMylanta]

@@jtlegionnaire6310 IMO 14.5 pinned really isn’t that much shorter than 16, and you’re giving up a little velocity and the ability to swap muzzle devices without destroying them

[@Doc41295]

I really think the 13.7 is underrated. It might only exist for the legal reasons but it's a wonderful length. Super handy, good velocity, smooth recoil impulse, and plenty of rail space.

[@Minutes-Mils]

100 percent, my 13.7 is awsome, shoots 1 moa with 77 grain ammo, still supersonic out to 700+

[@JEJAK5396]

Eagerly awaiting the 13.8” length. Just to keep the ATF Fudds on their toes.

[@Dominik189]

13.7 doesn't exist for legal reasons. It exists because the Brits felt the 14.5 was too long for their SAS guys. They're just as wrong as the Army was and is.

[@The_PotionSeller]

Love my 13.7. I keep it slim and light up front and it handles as well as a sub machinegun

[@PureCountryof91]

And you should be able to run a mid length gas system with an adjustable block in order to tailor recoil, reliability and obviously set it for a can

[@paulwuzhere]

12.5, mid length, front sight post, and it has reliability quirks. I love it. Favorite Hop AR.

[@Hoplopfheil]

It's not the worst gun I've built

[@SmithASB]

@@Hoplopfheil yeah that 308 PTR-ptsd

[@Eroc556]

11.5 love here…… cant change my mind yet

[@ringneck7500]

@@Hoplopfheil if 10.3 is bad than why do the have a proven track record.

[@mghegotagun]

12.5 mids scare me. Wish IWI would just sell their uppers since they apparently got the ports right.

[@kandaceblankenship9134]

Hop is an absolute beauty. He has the tone of a boring teacher that's impossible to learn from but somehow it's the exact opposite. Insanely good teacher and has become one of my favorites.

[@jeffpraterJSF]

In 20 years he could play the teacher in a Ferris bueller remake

[@iCookCrystalMeth]

He’s basically the Paul Harrell of youtube

[@tigerstrip1954]

>buys a 12.5 barrel for black friday >Hop literally the next day

[@alexisdetocqueville9964]

Calling out trends as you see it - never change, Hop. Personally I only run pistol lengths with 300BLK and 5.56 at 16". The AR/5.56 was designed around a 20" barrel for a reason.

[@Thenikksmeister]

Exactly! It’s what 300BLK was made for

[@sensitivegangster02]

always here for triarc slander

[@BJTE6]

Hundreds of hours of research and testing boiled down into bite size videos. Love the knowledge dumps

[@ERRGSU]

I don’t comment on YT videos ever, but just wanted to let you know I’m a huge fan of your candid approach. Truly, I really respect you opinion brother.

[@JCG105]

You know...I really didn't think I cared about this subject, but I found myself enthralled. You're an ace, Hop. Absolute ace.

[@MellowFellowOfYellow]

The gas port sizing is definitely at play for this length. LMT’s take on the mid-length gas 12.5 is well regarded for how smooth it is, and it runs great unsuppressed but was designed with full time suppressor use in mind for TACPs using their 11.5” “Specwar” upper

[@BoxdHound]

For sheer reliability that's the way to go, but the barrels are so heavy you end up giving back some of what you gained by shortening in the first place.

[@DinoNucci]

14.5 is the correct answer

[@SuperXrayDoc]

I have a specwar and it's insane how smooth it is. However if you're not getting a 12.5 with a midlength gas tube then just get an 11.5. With my RC2 on it it is also amazing

[@SuperXrayDoc]

@cougar0034 the heavy barrels are done on purpose to allow you to use the gun for longer periods before it gets super hot. I'm able to go through about 4 mags of my LMT suppressed before it gets too hot to hold vs my BCM which gets too hot in around 2-3 mags suppressed. It's worth it for the extra weight imo

[@flonga1]

I plan on getting a 12.5 Specwar upper. Any mods, tweaks etc you made since first shot?

[@stxnational9102]

12.5 Ballistic Adv w/ aero adjustable gas block, H1 with an AR10 flatwire spring. 3 years and a few thousand rounds later, it's been pretty great. Suppressed and un-suppressed. Good video 👍🏼

[@merdith6]

My build is very close but i use a sprinco blue spring.

[@2Ajosh]

What gas length?! I’m building my GPR ?

[@larsmurdochkalsta8808]

I feel like the 12.5 is still arming sword territory for me. With 14.5 SBRs being the bastard sword and 13.9-14.5 pin and welds are a really great analogy for the messer. Messer meaning knife, despite it being the approximate size and function of a sword. It's a similar workaround historically, we can't have SBRs but we can have a smaller overall length If we construct the "barrel" differently including the muzzle device. I believe the Messer was because civilian ownership of "swords" was heavily restricted. But "knives" were not particularly restricted, so they built a really long "knife" with a long handle. But what made it a "knife"? The construction of the handle. It is an extended full tang, with the extended portion of the tang serving as an affixed "pommel". With the gRiPzOnE being a riveted slab on either side of the tang. Like a kitchen knife basically. There's also other examples like the ninjato off the top of my head but I think that's enough autism for one comment. TLDR: people have been doing weird shit because of dumb weapon laws quite possibly for as long as dumb weapon laws have existed.

[@mpkp2011]

I thoroughly enjoyed reading this comparison

[@rtydht45r5]

This was a good read, have my reddit silver good sir 🤓

[@mpkp2011]

@@rtydht45r5 😂😂😂 thanks for the updoot kind stranger!!1!

[@1014p]

Um, equating a rifle to a sword is stupid. Swords dont exceed 1000 fps plus unless your a supper dupper hero type or bad ass mystical warrior. That said, yes 14.5 pin and weld largely born from stupid rules, not laws. Just AFT apparently is answering to nobody but puppet master. The 5.56 is just not the best round anyway for this or really at all. Cheap ammo is main reason people keep trying weird shit on builds.

[@ohioman4646]

Fellow HEMA enthusiast

[@mbiker345]

I can’t wait til the internet decides that 6” barrels are fine and it’s completely fine that it’s moving same speed as 22lr. The mental gymnastics will be a treat to watch.

[@YumekuiWRX]

Funny I'm actually in the middle of rebuilding a 12.5" upper into an 11.5" because my can got out of jail. Switching over to dedicated suppressed I was running into all the gassing issues you spoke of (carbine length) plus the weight balance started to get iffy. I think GT got it right when he said 12.5" for unsuppressed, 11.5" for suppressed.

[@LyleH-13]

Loved this video. You really seem to have your finger on the pulse of what people who clearly don't actually own a 12.5 are talking about online. Which I appreciate. It really does beg to go shorter or just go for p/w

[@ALovelyBunchOfDragonballz]

Personally I split the difference between an M4 and MK18, two well proven and appreciated configurations. The 12.5 also dates back to at least operation gothic serpent, it's nothing new.

[@SuperXrayDoc]

I own an LMT specwar which is a 12.5 but it has a midlength gas system. It's amazing how much of a difference it makes over a carbine gas system especially with a suppressor on it. However, I would still recommend an 11.5 with a carbine length over a 12.5 with a carbine length. Only a couple companies make the 12.5s with a midlength but they're so worth it. Also, with the issue of cycling unsuppressed I highly recommend a BRT eztune tube for 50/50 use. It's amazing how it fixes all the issues

[@TXARMYVET89]

We deal with with the tuning side here everyday at Sprinco. We help fix about 99% of tuning issues just with our springs. Not a spokesperson just proof is in the pudding. Great video.

[@OFFICIALUND]

I am a proud (and prolific) customer of Sprinco! Red, Blue, Orange, white, “hot white”, etc. I have them all (and lots and lots of blues). The one thing that tuning with a stiffer spring does, though, is accelerate the return of the BCG. That can be problematic in extreme cases, causing the carrier to override the magazine. It’s happened to me a couple of times… and it took me quite a while to figure out, TBH. I have Sprinco in all of my rifles (except one…for reasons), and also have the bolt reliability kits, too.

[@kxkxkxkx]

Braided super 42 buffer from geissele is the preferred solution 🗽

[@gmenendez9569]

Another well done video!! Answers many questions as always. Thank you my dude.

[@mynameajeff226]

This is most definitely the most helpful of the 22,691 videos on barrel length. I run a 12.5 with a MI rail as well but with the standard carbine gas.

[@SteveM-426]

Man! I love the way you get to the Point and Appreciate your Insight. Well Done!

[@canderson2478]

I run a 12.5 mid length Triarc track 2.0 (one of the original ones before they engraved the patent # on them) with a superlative retrofit piston kit. I keep a YHM turbo k on it all the time. Super soft shooter and super accurate with all types of ammo. I’m very happy with it, it’s my go-to.

[@navyman8903]

Solid video man. I'm glad you hit some of the points, because people needed to hear it. Especially the 12.5 mysticism.

[@smokingcrab2290]

Bro i love your reviews. They're extremely no nonsense and take all the crucial variables into account. And you deliver it all with great word economy and wit. I'd have a beer with you any day.

[@aggrodkreg4321]

This video inadvertently answered a question I had about LVPOs on 1.93 mounts for use with a FSP. The discussion about the 12.5" barrel was nice too. I've only ever stuck with 14.5" and above because of aforementioned laws.

[@LyleH-13]

Hop is good at dropping those nuggets of random questions he knows we have, because he has them too.

[@lucastonoli3256]

Gas port size is another variable to consider that is often not even considered by manufacturers. Faxon is known to have pretty large ports. I get that it won't affect dwell time, but still, something to consider.

[@bryanst.martin7134]

Getting it lined up properly helps a lot.

[@ALovelyBunchOfDragonballz]

It's likely due to customer demand. DD did the same thing on the MK18s. They had a smaller ~.072" port original, worked fine suppressed and unsuppressed with 5.56, but then people demanded to be able to cycle their russian steal cased through their specialized weapon so DD said "fine" and opened the ports up to ~.080".

[@leeroyjenkins1127]

Informative as always. Hop is one of the few KZbinrs left who just lays down facts and when it's an opinion makes it known its his perspective

[@pahriia]

Running an Aero Precision M4E1, 12.5 Complete Upper - Carbine length gas system with H3 buffer. I have thousands (maybe 2K) of rounds through it, not a single malfunction, ejection at 3 O'Clock. Smooth shooting and runs everything from XM193 to M855 perfectly.

[@rilesmattix5217]

I have the exact same experience (albeit I've shot much less out of it)

[@brojelio1518]

The balance and feel of a 12.5 makes it my favorite to shoot out of my lineup of 10.3, 14.5 and 16. Running same upper as shaine frederick above. Smooth n soft

[@pd5156]

Have You ever use suppressor? i'm thinking about this 12,5 carbine upper.

[@ramsaybolton7464]

I’m in the process of locating an M4E1 now with Aero. Having difficulty. Going to go with a 10.5 inch barely because it’s to defend my warehouse from bangers. I’m security in LA

[@dingdongheadyuue]

Unrelated to this topic, I just wanted to say I just subscribed and never in my YT experience of getting useful/applicable information for either DIY or purchase, have I ever been more impressed by your channel. Your ability to provide no nonsense and truthful facts about the product or fix, in a professional, credible way while at the same time compelling with just the right amount of sarcasm is worth watching every bit of your videos without skipping forward. Very Respectfully, CWO4 Weps, USCG Retired

[@dingdongheadyuue]

PS, BRAVO-ZULU

[@brazzy1467]

I have the Roscoe 12.5" barrel and it's a great setup and I only use it for hunting. Now my end of the world upper receiver has a Noveske 12.5" CHF Chrome lined barrel on it. It's accurate and durable. Awesome video

[@motoman5208]

Just got a 12.5 roscoe bloodline myself. Pretty excited to try it out

[@Apocolovids]

I run an 11.5" Faxon Mid-Length Gunner barrel with an adjustable gas block and H3 buffer. I pretty much only run it suppressed, and so I've never had any issues with it. Softer recoil than a 16" carbine-gas by far. I've been planning a suppressor upgrade for a while (I currently have a cheap direct thread can on it now) to the Xeno + Nomad system. I'll have to keep in mind the gas issue were I to actually shoot it with the bare muzzle device.

[@CleanCivilian]

I ran this exact setup but matched with the Vltor a5 system. It was titty city! Did not like steel case, would key hole, but ran everything else butter.

[@ReverendMeat51]

An 11.5 middy? Damn, back in my day 14.5 mids were controversial

[@Valorius]

I use the same Barrel unsuppressed with an H3 and it runs outstanding.

[@Valorius]

@@ReverendMeat51 I think most of the time the things the gun guys argue about are almost totally meaningless in the real world.

[@ReverendMeat51]

@@Valorius Truth

[@oldscratch3535]

I've been eyeing a 12.5" build but I already have a 13.7" and 16" upper and the 10.5" BRN-180 so it seems like kind of a moot point. I'd just be satiating my lust for more guns which I suppose is a valid point. Thanks Hop. You just talked me into building a 12.5" upper.

[@DinoNucci]

14.5 is the correct answer

[@CP-xo6yb]

A list for more guns could be seen as a desire to protect those that matter to you. That being the case you could never have too many as they could always be hidden in responsible areas for easy access wherever you are. If you run out of places I have several at my house you can use. 🙊

[@DinoNucci]

@@CP-xo6yb wat

[@jaksahn3370]

You're the type of guy who goes to McDonald's every day and talks to the counter for 20 minutes, doesn't order anything and goes home to eat soup. Get a life

[@CP-xo6yb]

@JAK Sahn haha I have no life due to 2 yound kids but I won't do McDonald's. I have a family to take care of. When random strangers attempt to murder you it tends to change your views on what would be effective. I want to disorient and get away to the 12ga and or long rifle depending how closely they are following.

[@JohnDoe-re1ll]

Good vid. The two issues you mention (scope weight + 5.56 barrel length) are relevant and have rolled around my noggin a time or two. In terms of weight, there as subtle outlier: barrel weight. Longer barrels are typically heavier barrels, and barrels from manufacturers like Noveske and Radian are pretty heavy. I had a Noveske Afghan 5.56 gun with a (pinned) 14.5" barrel that was quite front heavy. The answer I came up with is a 16" Proof barrel in .223 Wylde. This answers a number of issues in that is extremely light (and accurate), offers good ballistics, affords a reliable gas system that won't beat your firearm to death, and is considered a rifle so I don't have any NFA issues. It also accepts 5.56 and .223 ammo just fine. Along with the added rail space of a 16" barrel, the Proof reduces the overall weight, making allowance(s) for an LPVO (something I quite like on this type of setup). With that said, I saved my pennies for a Swarovski Z8i. This scope is extremely light (just over 17 oz.) for what it is (my VCOG is 23+ oz. and you can feel it) and can help me identify and engage targets at distance. If I want to go shorter with this setup I could add a LAW folding device (my experience has been they work just fine). But that isn't what this gun is for (what's the mission?). For a, "shorty," I have a B&T APC 300. Unlike the 5.56, 300 blk was made to fire out of a shorter barrel and therefore does not suffer ballistically (as much) being fired from the APC's 8.7" configuration. Too, the APC is a short stroke piston-driven gun. This means you don't have to worry as much about the gas system functioning properly. As far as a suppressor is concerned, I have gone with an OSS. As many know, the OSS has a baffle system that gasses out the front and therefore doesn't screw as much with cycling of DI guns. I have installed an OSS adaptor on five of my guns so I can set them up to run reliably/consistently on the same can. This saves from a cost standpoint, and keeps me from growing old waiting around on the BATF. Hope this helps.

[@f308gtb1977]

Great info as always Hop!

[@davidsirmons]

The squeeze bore is a solid idea. It's easy to dismiss triarch's attempt at one, but there's more to consider with such barrels other than bore diameter. There's research to do with twist rate (constant vs increasing rate), having a recessed crown or not, quality of the blanks, quality of the boring machine, heat dispersion and its required machining variants, and likely even more that I haven't thought of off the top of my head. The ceo of triarch is notorious for mis-managing companies to the point of disaster, so their squeeze-bore barrel 'failure' was par for the course. They likely bought 1000-10,000 blanks, had bore cutters made to size, and simply went at it. That's not how to do it. I had the same idea, but it would take at least 100 finished barrels at such reduced bore size to properly test with ammo, at distance, longevity, etc. and might even demand a special higher-carbon steel than normal barrels to survive past 5000 rounds.

[@evanacey1414]

Love my Triarc Track 2.0 12.5” mid gas barrel… I don’t get the tightest groups of all time with it (2 MOA w/ M855, occasionally I’ll get a sub MOA group with match ammo), but it is BY FAR the softest shooting upper I own and is gassed to absolute perfection. It runs like a damn sewing machine ffs.. I get that barrel manufacturers are judged by their consistency, however, and for every barrel like mine there were apparently 1 or 2 that didn’t live up to the hype.. Guess I was just lucky. It’s in a Mega Arms billet upper and I remember having to heat the receiver extension with a torch just to be able to seat the barrel extension all the way to the alignment pin when I first built out the upper. I’m sure that tight fitment plays a big role in a barrels potential for accuracy as well.

[@williambasilone]

You're right on the money when it comes to gas tuning. I have a BA Hanson 12.3 and with an A5 buffer system and a Bootleg adjustable BCG I go from using an H1 buffer and completely closed BCG when shooting cheap steel to an H4 and completely open BCG when shooting full power 5.56 suppressed.

[@jonlewis758]

I have a Faxon 11.5” mid length barrel with an aero precision adjustable gas block. It run’s excellent especially runs great with my Alamo15 in it. It’s an all around excellent barrel for the price and the shortest barrel you can get with a mid length gas system. It shoots super crisp and there’s hardly any recoil. I’d recommend it to anyone. You won’t be disappointed.

[@helixx92]

OSS now HUXWRX suppressors severely simplify gassing issues with all rifles not just ARs. I got one it works great on my ARs my AK and my PTR91

[@MikeA817]

just the video I needed to see as I decide to start my own 12.5 build

[@jeremywatson9129]

I have a the same Viper gen 2. And I love everything about but the weight. Not over loaded with features but delivers on the features it has, but the weight.

[@Osprey1994]

Glad someone else is calling out Triarc. I did some digging after hearing people gush about some of the OG builds they picked up and quickly realized that at a certain point they exceeded their ability to fulfill orders and instead of making smart business decisions they made a bunch of bad ones that ruined their image. PS. Supposedly the hopes with the Roscoe barrel is that internal barrel surface is nitrided which from my digging seems to be pretty competitive with chrome lining except without the potential accuracy issues. I can't be sure though, but I do know that I have seen a Roscoe 4150 CMV nitride barrel that was autopsied after 26,000 rounds on a full auto lower that didn't look terrible. So I guess my hope would be that the 416 Stainless would impart some of the accuracy benefits and gain some of the longevity from the nitriding process to maybe get you into the 13-16000 region. Hopefully someone will shoot the snot out of one of those barrels and report back on it.

[@blodus4521]

Triarc is one of those companies where I can't trust opinions of their products because everyone seems to 'know a guy' who works there or waits over a year for stuff. Hard to tell how good their QC and CS is when regular consumers have trouble getting the product.

[@GrayM84]

I was one of the lucky ones and got a 12.5 Triarc right before their reputation went to shit. Took about 3 months to get mine back in the beginning of 2020. I will say though, its a great rifle. I love shooting it and everyone else that has tried it loves it too. Soft/ very flat shooting and very well built. It's a shame they made such bad business decisions.

[@brandonhays9900]

@@GrayM84 bad business decisions such as?

[@slister1911]

Nitriding stainless actually reduces its corrosion resistance. And hard chrome is much more resistant to hot gas erosion than nitriding.

[@sribble1]

FWIW Triarc states you can expect a 15K-20K life for all their Track 2 bbls

[@TsunTzu]

I...absolutely love my 12.5 Criterion SBR Light build. Seemed like the best possible compromise of length/velocity. Carbine gas, yet still really nice. Adjustable block helps, but the port is already pretty smallish.

[@adamg574]

I’m trying to decide right now between 11.5 or 12.5 criterion. Have you done any chrono on it? I’ve never shot or handled a 12.5 does it feel too long for CQB work?

[@TsunTzu]

@@adamg574 Unfortunately, no chrono. I'd suggest checking out velocity comparisons. As for CQB? 100% fine. 10.3 is going to be better, of course, but 12.5 is more than acceptable.

[@kid-hudi]

@@adamg574 I have the same Criterion 12.5 and I love it to death. The length is perfect. It feels very handy and pointable. I can move through a door fine. I can still take it outside and go 300-400m easily and comfortably with it. Going off what others have said, it's only a 50fps difference from a 14.5. Is it the sAmE vEloCiTy? No (Hop is being so damn literal here). But it's so damn close that the velocity discussion becomes negligible within the neighboring barrel lengths above, and the other benefits like weight and mobility are more pronounced. Even with this not being the CORE series barrel that every shits their pants over and is always sold out, it's still balanced very well despite the govt profile. I have my lights and sights and shit out front and I like the balance still. Taking my thumb and index finger and pinching the pic rail, the balance point of the rifle is at T11. Just a few rail slots back from the rail on the upper receiver. Perfect balance on a rifle IMO. The 1-8 twist .223 wylde, means I can shoot common 55gr really well (and it actually prefers 55) or 75/77gr ammo very well and .223 or 5.56... literally anything, and every thing very well. It's the tightest grouping barrel I've personally shot. Never shot it suppressed, so I can't speak to that. You can always adjustable gas block a port size but you can't adjust dwell time. Carbine length is fine. People nit pick and bitch and worry about the weirdest shit. Nothings perfect. Just learn to live with the pluses and minuses and adjust yourself to them rather than adjusting your rifle to you to the point of wanting impossible nitpicky shit. The 12.5 is about tempered balance. It's not "general purpose" as much as it just sits right in the middle (which is Hop's main bitching point). So any critique of that will be about wanting to move to something more specific. "I want more velocity." so you move up. Or "I want shorter length" so you move down. But then when you do either of those and get more specific the next move is to complain about wanting more balance. So then you try to become more generalized. Then you try to become more specific again. Then more general. It ebbs and flows constantly. Just pick a fucking rifle length. Set it up. And knock it off with these discussions. God damn people. It's never ending.

[@techti8792]

​@@kid-hudi you have the hybrid criterion?

[@yellowdog762jb]

I've had good luck with several builds in multiple calipers and various barrel lengths using the Superlative Arms Adjustable Bleed-Off Set Screw Gas Block. You can set it to vent some of the excess gas out of the front. I mostly use mid length gas systems.

[@ethan5.56]

I’m running a Rosco k9 12.5 with their patrol length gas system. It runs great unsuppressed but I don’t own a suppressor to see how it runs suppressed. Their patrol length gas system is between carbine length and mid length. Great video as always

[@theimmortal4718]

In combat, we always prioritize threats from near to far. Threats in front of you matter more than ones on the horizon. The reason short guns are popular in combat is because suppressors are becoming standard, they're quicker to index, they're lighter, and so much fighting is up close. Trading velocity for those reasons is generally considered acceptable. Longer range threats are engaged with dedicated guns for those uses.

[@sterlingcampbell2116]

"Longer range threats ate engaged woth dedication guns..."... yeah, 16-20" AR/m16s. 300bo/762 better for close by

[@theimmortal4718]

@@sterlingcampbell2116 m240s, 60mm mortars, Gustafs, M24's.....

[@vicnighthorse]

Well done. Entertaining and informative as usual. I don't even own and am probably not getting a 5.56 and I still found this video a compelling watch from start to finish.

[@RADIOACTIVEBUNY]

An AR at this point is such an idiot proof prolific and effective general purpose rifle that I’d say everyone should have one. Don’t need a Gucci one though.

[@usnclark]

If you keep watching hop after you get your first AR, I hope you like raamen. This shit aint cheap

[@talltale9760]

If you live in burgerland I highly recommend at least one AR-15. It’ll fulfill 90% of your firearm needs. A compact 9mm pistol a 12 gauge pump shotgun and a 5.56mm AR-15 is the holy trinity imho. Throw in a .22lr pistol and rifle and you essentially have everything you could ever need.

[@vicnighthorse]

@@usnclark I have ARs. Just in freak chamberings. I am just not pragmatic enough to use standard cartridges. I am not much of a shooter, just someone that likes to fiddle with things.

[@vicnighthorse]

@@talltale9760 Thanks, but I am just an peculiar old guy that is armed but with oddball firearms that I didn't choose very rationally. I know what the wise choices are (partly from watching guys like Hop), I just don't make them. I chose the chambering for my favorite AR because the cartridge looks like a mini version of the German 20x82. One doesn't recover from reasoning like that😏

[@50shadesofcerakote]

Whole time I was sitting here thinking you could probably fix most of your gas problems with the BRT gas tube, then finally 10 minutes in you finally said something about it haha

[@brandonrupp5880]

I made my own 12.5 upper out of a PSA freedom upper that I cut down and drilled out the gas port. It has been reliable with 5.56 unsuppressed.

[@rickm4295]

I thought the trend was suppress the 11.5 and keep the 12.5 a dedicated un-suppressed gun. Thats what I heard anyway. I like my 11.5 , great range toy

[@sendit7922]

I heard that from Garand Thumb, which does sound practical for the roles of those shortys. What I didn't know was that you get the same velocity out of a 14.5 using a 12.5. If thats accurately true, then thats awesome.

[@joejohnson4183]

@@sendit7922 Did you not see his graphs because they are not the same velocity nor ft. lbs. That is like saying the 10" has the same velocity as a 12" , they don't .

[@benjamin3290]

That’s not a bad way to go. I have a suppressed 11.5” SBR for home defense and a 16” for everything else. The 16” is a mostly-stock Geissele SD and the SBR is a Franken-Geissele that I built. To me, that duo makes the most sense for versatility and compatibility.

[@K-bob_45]

@@joejohnson4183 go chronograph a few. The amount of velocity loss from 14.5 to 12.5 falls in the margin of fast vs slow barrel. There is less tube so it should be slower but you can certainly have a 12.5 that is as fast as a 14.5.

[@K-bob_45]

I bought a 12.5 for a do all and a SF MINI 2 to pair with it. It’s about the same length as an 11.5 with a full size RC2. You just pick up a little rail space and velocity. Probably not enough to matter in most cases. Definitely looks the best on a spreadsheet though so it’s objectively right 🤣

[@Valorius]

I literally just got done watching a video two days ago from a Delta Force operator who said that the effect of range of a 10.3 in shorty with Mark 262 mod 1 is 500 yards. He said they used them to 500 yards in Afghanistan all the time.

[@spearthumb68]

45yds frag with fmj is definitely not relevant for people who have options.

[@Hoplopfheil]

That's adorable considering that the velocity of a 77gr TMK from a 10.3 at 500 yards is probably going to be comfortably under 1500 fps, with ~2 feet of wind drift.

[@spearthumb68]

@@Hoplopfheil mk262 wasn't even tipped. I think it was Dorr and Coch from tactical hyve.making that claim. They're ex SEALs.

[@Valorius]

@@Hoplopfheil It was 9 hole reviews, just this week, in their M4A1 review. The claim was made by Jeff Gurwich, US Special Forces, who has a channel called Modern Tactical shooting. He makes the claims starting at the 14:30 mark, when he says with the 14.5" m4a1 block II upper they *regularly* shot to 650 meters in ARM. I recommend watching it, it is also highly informative.

[@Valorius]

@@spearthumb68 No it was 9 hole reviews.

[@KarlHungus.]

Really liking the idea of direct thread for future endeavours. Just think of all the savings to be had...

[@honeyblunt5150]

Can never get enough of your dry humor and deadpan delivery

[@megastarsport]

20” M16 gang laughs at concepts like “handy” and “light weight”

[@alastor8091]

If a couple of pounds is heavy to you, I need to wonder why a woman with atrophied muscles is spending her money of guns instead of medical treatment.

[@alastor8091]

@Jesse Robinson >what is a suppressor? >what is a peq? I didn't know that you couldn't use them if your barrel was over a certain length.

[@grben9959]

An M16A1 and M4A1 are within a few ounces of each other for weight. Barrel profile matters as much (or more if we're talking bull barrels) as length for weight. Neither matters as much as how much stuff you're bolting on the gun.

[@spearthumb68]

@@jesserobinson838 what?

[@babeeeTrex]

@@grben9959 this.

[@michaelblacktree]

Actually, the 16" barrel with mid-length gas system is the best setup. Because that's what I have. 😛

[@ethanwiley7605]

I thought my 16" mid length kicked too much for an ar till i built a carbine length 12.5" and that makes my 16" feel like a dream

[@michaelblacktree]

The 20" barrel with full-length gas system is even smoother. I love shooting my A2 clone, because of that.

[@ethanwiley7605]

@@michaelblacktree i have a cousin that shoots competition and he had a 20" with a break and geissele's most expensive trigger and it was actually like a .22, felt like a damn video game

[@talltale9760]

@@ethanwiley7605 I have a 20” build using a criterion core barrel and a surp arms adj gas block. Has essentially zero recoil and that’s with just a basic A2 flash hider.

[@cerebralfirearms]

Love my IWI Zion 12.5” with mid length gas system. She will have a nice nomad 30 once Carol decides to sign off on it along with superlative adjustable gas block, blue springco spring, and H2 buffer. Perfect setups do exist, just takes time, money, and tuning.

[@andrewpeterson549]

+ 5 points for the Wolf A1, 12.5 piston upper runs like a well tuned 16 so smooth so nice can or not 👌

[@Minutes-Mils]

13.7 gang, BA barrel. still get around 2900 fps with Winchester m193 Still got about 2550 with 77 grain ammo In combination w a k can it would be great, but I got a full size sandman s, so it's back to a 20in barrel w the can

[@JamesGreenbaum]

If you really want to get the most out of a shorter barrel AR then the solution is quite simple -- build a platform that operates with cartridge that is optimized for the reduced barrel length -- .300 Blackout. 😊

[@ianxtreem]

Nice video. Love the way you are no nonsense.

[@burtlandcastor8359]

The MI 2pc handguards are great. I've run an upper with a Criterion hybrid carbine 16" and the MI extended carbine HG. It's fun when buffered with an A5H2. Plenty of rail and velocity.

[@Rakadis]

You Americans have it hard. I just go with the length of the most common military AR in my country. This lets me use military ammunition and makes parts easy to get. Greetings from Norway. And the HK416 says hi.

[@InexorWoW]

14.5" with a pinned/integral is just so good.

[@billh1713]

Good job! Thanks for the content always enjoy well thought and informative videos..

[@samt5716]

Thank you for the disclaimer at the start Hop.

[@lordofthepigs888]

People should not be asking “what’s the lowest velocity I can get away with?” And instead ask themselves “what’s the longest barrel I can get away with?”

[@Hoplopfheil]

Hey I like that.

[@mc-sillix961]

Long as needed but short as possible

[@theamericancristero7390]

As a hand and a half sword owner, I approve of this title.

[@joshshepherd5660]

I did a "gordon carbine" build using a 12.5 barrel. 4150 cmv. Carbine length gas system.1/7 twist. I cannot for the life of me remember the brand but i got a great deal on it because someone had ordered it in the shop and never picked it up. If i remember correctly I went with the H2 buffer. Running an A2 upper pinned fsb and a silencerco 3 prong so i can use my superbly oversized silencerco omega 30 cal can on it. No issue what so ever running the gun. Can or no. She runs smooth. A smidge over gassed but nothing I didnt expect. It is for sure my favorite 5.56 gun to just shoot running drills. m193 runs about 2800-2890ish. Oddly enough it shoots the piss out of some hornady 55gr flat bas soft points! I duno why but it loves that bullet.

[@rcrites]

I've got a 14.5" because I apparently can't read and bought one by mistake because it was on sale. Got it pinned with a slim flash hider so I can still remove the block and nut. It works

[@l337l0gan]

Hop, I must comment that the rosco 12.5 k9 with the patrol length gas system is 416r, but it is fully nitrided inside and out. Although I agree it is not going to have the longevity of a chf chrome lined barrel, I do believe it will last much much longer than just a regular 416r barrel. Cheers and thanks for all the great content!

[@shaggnar2014]

The profile is also supposed to help with avoiding heat retention, but I'm not sure how much that matters

[@BigTexOrdnance]

We have sold a ton of the 12.5 K9s

[@LyleH-13]

The difference in longevity of nitride vs chrome is vastly misunderstood. If you're to the point you are wearing out either barrel, the cash to replace it pales in comparison to the cash spent on ammo. So fuck it. run whatever.

[@johns9888]

@@BigTexOrdnance expected round count on each?

[@BigTexOrdnance]

@@johns9888 that would be a good question for @roscomanufacturing5188

[@fullm3taljacket]

This is why I went with a Wolf A1 piston upper when I wanted a 12.5". Unfortunately still got just as much gas to the face as a DI gat, so it got sold off too

[@sackychin6267]

Because the majority of blowback is from the barrel not the gas system

[@spencercross3867]

I cannot run a can on my 12.5 wolf.

[@trainer2448]

Great analysis.

[@aaron.Idaho.preparedness]

I cut and threaded a Bushmaster barrel with a front sight base to 11.5 I’ve done all my tuning to work with a Rex Silentium suppressor using the Vltor A5 buffer system (rifle length) and SpringCo green spring. Not at all gassy and VERY soft recoil. I’m also running the Vltor CASV handguard…it’s perfect

[@Zel_eo]

Great video as always Hop. I run a SA piston kitted 10.3 specifically for the gassing issues you talked about in the vid. Got super tired of mucking about with buffer, spring, and bcg weights so I just went the "affordable" 416 route. Might try one of those kits out some time, would love to see what you think of it.

[@LeifyGuy]

It's funny because I slapped my 12.5" with random parts I had on hand, put the resonator k on it, and was fully prepared to battle figuring out how to get it to cycle,but instead just ended up getting everything right and ended up with a decently well running build lol

[@jackchan3235]

That pause in the beginning was marvelous

[@mrwagner924]

I enjoyed this riveting information given in a somnambulant tone. Very educational and soothing for meditation.

[@CWHolleman]

13.7 + pin/weld edges out the 12.5 in my opinion.

[@stratofear502]

Not having to worry about the latest ATF ruling is worth it for me

[@Barnes-ml9wg]

@@poopoo7705 basically

[@Minutes-Mils]

100 percent

[@airborneivan]

I love the 12.5. Definitely a good blend of attributes. I have two, one from Triarc and the Rosco K9. Both run great. I did have some issues with my first triarc barrel but it was replaced and no issues since. Definitely odd that they both run .076 gas ports but at different lengths. I will say, in my testing, with 55gr ball the average velocity loss from 14.5 to 12.5 was 50fps. As for the Rosco K9, Aaron did state that his reasoning for the 416r barrel was to put accuracy first. Good thing it's nitride inside and out. He also did say they may utilize the patrol length in a barrel more suited for hard use in the future.

[@duroisgawd]

nitride does nothing for stainless steel.

[@airborneivan]

@duroSIG556R that's not true. It is harder to nitride and maybe not as effective as nitriding a 4140 or 4150 barrel but it can be done successfully and help prolong the life of a stainless barrel. Though I will admit that I don't know which process of nitriding is necessary for it to be successful on stainless.

[@joshuakern1274]

@@duroisgawd I came here to say this but knew in my heart that it had already been said.

[@crashdsnowman1]

@@duroisgawd Nitride makes a stainless barrel that is 30 Rockwell about 60 Rockwell so twice as hard and lasts much longer.

[@duroisgawd]

@@crashdsnowman1 not when it comes to stainless. The only benefit nitride gives yo a stainless barrel is corrosion resistance. Also if you listen to the video, the chamber is chromed. No other treatment to the bore.

[@ghill1010]

Thanks so much for the no BS, to the point vids!!!!

[@EdgarCorona]

Fantastic video, much appreciated!

[@Kross8761]

I think a good option for your 12.5 might be to nix the FSB and use a rifle speed adjustable gas block, they give a super wide range of gas settings that are tool-less to switch between and it's still a pinnable block that you can be sure won't move. This way you can find what setting is ideal for unsuppressed and suppressed and mark each and be able to swap between them easily, also your phantom hill laser would work without the FSB on the rifle. I absolutely love the rifle speed gas block, I love that it's completely tool-less to adjust and I can turn my rifle into a bolt action by completely shutting the gas off, or turn it into what feels like a smokescreen generator for those tactical batman getaways (just a joke) I get that that setup kind of makes the rail you chose pointless, and you do have to kind of do some figuring beforehand and figure out how long your barrel length and rail length need to be to give you correct access to the switch on the gas block, but they have a page on their website that lets you plug in barrel length, gas system, and rail length and tells you which of their selectors is compatible.

[@cbulldog22]

ill rebut that with they cost 200$ and at that point you may as well just buy a different barrel

[@Kross8761]

@@cbulldog22 true enough about the cost, but barrels have one gas setting, they don't change, the gas block is what changes the amount of gas flow. So if you're bouncing back and forth between suppressed and unsuppressed and want to stick with a standard gas tube length then an adjustable gas block is necessary. And why not go with the best one?

[@therealmccoy9948]

@@Kross8761 And it's not like the other shit on his gun didn't cost way more than that gas block.

[@Kross8761]

@@therealmccoy9948 very true, I also like that the riflespeed gas block is designed to be cross pinned so it's just as durable as the old school FSP gas block. I'm not a collector so I don't have a bunch of guns, every single one of mine has a purpose and they're made as fail-proof as I can reasonably make them. I don't begrudge anyone who does have 12 different AR's that's 100% their right, but I'd rather have 2 or 3 that are as 100% rock solid as I can make them. I have a 12.5 setup for 0-300 and then a 16 for 0-600 and then I have a bolt gun for long range stuff, the only thing I've really "cheaped" out on is glass for my long range setup because I'm not skilled enough to know what I really want or need yet, and my scope is decent, and certainly good enough to learn on and then upgrade when I have a better idea of what I'm actually looking for.

[@therealmccoy9948]

@@Kross8761 In my experience you shouldn't worry too much about getting the top of the line glass. The scale of diminishing returns drops off hard after about $300. Spend $300-$400 on an lpvo from vortex or primary arms and you'll be good. It doesn't take much to get good hits out to 600 yards. USMC qual to 500m with irons.

[@paralyzdtheory]

20" pencil barrel IS, and HAS always been the best

[@alanniederlitz8630]

LOVE the optimism...

[@whiteywhiterson406]

Great vid. Packed with info. I always wondered why 12.5 wasn't more common I feel is perfect length for handling etc but I learned alot in this vid. Laws and velocity aside the tuning issues. Anyway learned alot great vid thanks.

[@MediumMango]

I've been running my 12.5 for about 7 years with 3 different barrels that have been shot out. First was the bcm kino, then DD 12.5, and a Sionics which im currently running. I have never had a tuning issue with any of them and could pretty easily get out to 450 at my range. 550-750 were definitely pushing it but only in terms of energy on target. I had more issues with my 11.5 bcms and Criterions than my 12.5s but thats obviously only one data point. If I could only have one rifle its my 12.5.

[@shaggnar2014]

I'd be interested to know what your thoughts on the Rosco patrol length gas systems are. They're between carbine and mid length for 11.5-12.5 barrels but being proprietary availability is always a concern

[@willtyler]

My 12.5" is a BCM "kino" with the middy front sight but the carbine length gas. Always thought it was dumb in concept because you have the weight of two gas blocks and one only exists to act as a front sight and handguard mount, but in practice I do kinda like it.

[@willtyler]

@Florida Man HVACR exactly.

[@asdfghjk2933]

@@willtyler How is your 12.5 gaseed?

[@willtyler]

@@asdfghjk2933 good question, I don't actually remember because I pay little attention after getting things running. I suspect it was spot on unsuppressed. I can't remember how it did with the SDN-6, but will be paying attention soon when my stamp for the RC2 comes in.

[@asdfghjk2933]

@@willtyler Thank you, I appreciate it. I've been considering that exact upper, but I don't hear as much about it as I do the 11.5" variant.

[@willtyler]

@@asdfghjk2933 there is a current kino thread on arfcom if you want some inspiration!

[@sidanx7887]

The humble joking way in which this discussion started is what got me - liked and subbed

[@mikelangford1835]

I feel like you’re one of my internet bros from the early 2000s. Great content.

[@mexygnome]

12.5 mids are one of those things that people are trying to make a thing again. happened like 5 years ago.

[@crashdsnowman1]

We have been making them steady since 2010, they are our second most popular length.

[@PresidentSkroob12345]

I see Comic Sans, I smash the like button.

[@stephenphillips7840]

Sir you are a wealth of knowledge!

[@palehorseone]

Good, useful content brother. Thank you.

[@senorFrog2032]

12.5 has luckily grown in popularity, so hopefully as time goes on they'll be more options for barrells and handguards. I think the reason it wasn't so popular was it wasn't short enough for the cool factor, and it's not long enough as you said to pin and weld like a 13.7 + velocity compared to that length. I've always preferred longer barrels even though I'm a shorter guy, never found length to be an issue as much as weight. Was never a fan of 10.5/11.5 for rail space. With a suppressor on 12.5 you're usually around the length of 18-20in which imo is very doable since 10.5 needs a standard size can imo, which you're adding around 6.5-7in for most common suppressor lengths. I'm thinking of upgrading to a CMT or ripcord industries 11.5 rail, I get a lot of acc. adjustability with that rail length. Just wish there were more bolt on rails like the agl and noveske(over-rated company imo) for IR zero retainability though. There's always compromise with builds, it's just right now 12.5 has more of them due to lack of popularity

[@CWHolleman]

Personally Ive never needed more rail space than is provided by an 10.3/11.5 carbine. 13.7 + pin/weld edges out the 12.5 in my opinion.

[@libertylivesin1776]

FCD or Centurion are the go to for me

[@jrk557]

I got a criterion 12.5 carbine core and it's been pretty great with a suppressor and an h2. I have a 14.5 pin and weld setup but have been running the 12.5 mostly at the range lately.

[@ExplorinInTheWoods]

I think the 12.5 velocity claim comes from the noveske barrels . There were some forum posts years ago comparing a 12.5 stainless steel noveske vs a chrome lined LMT 14.5 and with 77gr the noveske has just a hair more velocity than the LMT and was within 10-15 fps with m193 and m855. The Triarc barrels do have good velocity and are good barrels if you can get a hold of them.

[@jpowens2253]

Pretty sure it just comes from the velocity charts. It does not increase linearly with increased barrel length. There's spots where a 1 inch difference can either make a big difference, or almost no difference. If you look at the graphs, the biggest flat spot (aka the spot with almost no change in velocity) is the 12.5-14.5 zone.

[@asdfghjk2933]

@@jpowens2253 This is true, especially with heavy 75+gr bullet. My defensive load of choice (77gr TMK) gains an absolutely negligible amount of fps when going from 12.5 to 14.5.

[@Brimwald]

@@jpowens2253 yeah, it's not a myth. There is truth that 14.5 and 12.5 arent different enough in velocity to be worth the extra 2 inches.

[@TimberwolfCY]

"No such thing as a free lunch." I first learned the value of this maxim learning to shoot shotgun. Wise words indeed; thanks for the reminder Hop

[@tomhorn1876]

Good vid Hop! Informative!

[@PHIllip324]

I always regarded 12.5 as a good jack-of-all-trades barrel length: lightweight and compact, but acceptable velocity out to 300 yards.

[@babeeeTrex]

A 12.5 is good way past 300 yards.

[@sterlingcampbell2116]

​@@babeeeTrexfor punching holes in paper. Not for killing people

[@tesla82111]

@@babeeeTrex1000 yards minimum lol!

[@babeeeTrex]

@@sterlingcampbell2116 a 12.5 556 firing 55 grain rounds as much energy at 500 yards is a 357 Magnum Duty revolver at the muzzle. Get real bro.