DI vs Short Stroke Gas Piston - Thermal Analysis

In this video we use a thermal camera to discuss and observe the differences between direct impingement and short-stroke gas piston systems in two different rifles, the AR10 (Brownells' BRN10) and the FN SCAR17.
Special thanks to:
Matt Landfair of Primary & Secondary, LLC.:
/ @primaryandsecondary
J.W. Ramp for his filming and assistance:
www.jwramp.com/
InRange is entirely viewer supported:
/ inrangetv

[@straggler64]

Something I find really interesting and engaging about Karl’s delivery is his pace. Some presenters are really rushed and high energy, some are really sloooooow and laid back. Karl has the speed of the rush, but in a really consistent tone that gets the viewer all the way through the material at a good pace without feeling rushed, dragged out, or kurt. It’s a very unique style on youtube and I find it fits very well to the content.

[@sharpiesfishandphantoms]

Yep, regardless of subject matter certain presentation styles work better than others, personally i find the high energy rapid cut style to be annoying and sometimes hard to follow (a bit like a Michael Bey movie lol), i also enjoy it when the creators personality comes through and you can tell when someone is faking things. Big thumbs up to Karl for style, professionalism and personality.

[@n0tthemessiah]

He doesn't pause, fill space with "uh"s or "uhm"s; he's clear, concise, and effective even with what appears to be a (very slight) lateral lisp. It's honestly impressive and refreshing.

[@taiiat0]

sure - speed doesn't feel like you're waiting for the next sentence or segment, but there's also enough spacing to process everything before the next thing. i call this "knows how to make a presentation / be a speaker".

[@zendell37]

That is a very good point. He's well articulated, but quick. And he's easy to understand. Like, technically well spoken.

[@brabhamfreaman166]

Could. Not. Agree. More. It works extremely well in the (IMO hugely underrated) OWV historical series. Nothing feels overly rehearsed and is frequently delivered whilst moving (sometimes backwards - try it, it’s actually surprisingly awkward!) and/or gesturing to relevant landmarks/nearby ruins.

[@ducktapepilot]

Roadrunner makes an appearance above Karls right shoulder @ 1:18 (edit - corrected spelling on Karls name)

[@danielkaczynski9702]

Wile E. Coyote cannot be far behind.

[@rf9078]

It's Carl with a K

[@recceshoe6911]

Nice catch. Might be a Quayle though.

[@thomasfrank280]

Beep! beep!

[@lycossurfer8851]

@@danielkaczynski9702 actually he'd be waaaay behind. Road Runner got Carl as a bodyguard

[@Jetmech145]

RIP H&K SCAR-17. You will be missed.

[@vonWeizhacker69]

It was amazing! Such a great combination of engineering and beauty will most likely never be seen again. Sad.

[@christopherdean9684]

von Weizhacker such an amazing combination of malfunctions, thumb breaking charging handles, optic breaking rails, and much more violent recoil then needed.

[@herknorth8691]

You mean FN, right? Or is there a joke I'm not getting?

[@Jetmech145]

The first up load of the video had HK SCAR-17 in the thumbnail. They have since corrected it.

[@vonWeizhacker69]

@@christopherdean9684 I thought that one is only suppossed to say nice things about the dead.

[@omarrp14]

Oh mighty algorithm! Please accept my like and this comment as my tribute on behalf of In Range TV. Bless them with your algorithmic glory and bestow upon them many eyes and click so that they may grow.

[@rurouniad]

👍🏼👍🏼👍🏼

[@DeepCFisher]

Dont mind me, just here to boost the metrics

[@a-cell4564]

DeepCFisherman Same man, just here for the algorithm.

[@jamesdesrosier8226]

Mood

[@IRMentat]

How dare you.

[@Rockwood777]

White is hot and dark is not. Praise be.

[@skm9420]

It's supposed to be free world don't you know!

[@z71tina]

Cool to see a roadrunner over his right shoulder at 1:17.

[@RobinRobertsesq]

Hmmm, I would have said quail....

[@thaBurninator]

@@RobinRobertsesq maybe an anorexic turkey?

[@RobinRobertsesq]

@@thaBurninator their natural range is limited to Scottsdale

[@scottlloyd9762]

Its a quail. too fat to be roadrunner but perfect for quail. also the thing above the head is a quail only thing.

[@captainswoop8722]

Meep Meep

[@freddykisback123]

Original video was flagged by HK because you knew tooo much.

[@glandhound]

I thought it was because neither of those rifles is a H&K.

[@Octosnakes]

@@glandhound They're afraid someone will try it with the G36.

[@thecosmickid545]

Karl has such a super clear and concise way of speaking that I could listen to him y’all about organic chemistry without getting bored, and actually understand it. Really fantastic presenter and teacher.

[@troy9477]

The thermal camera footage is very well done, and helps to clearly illustrate the points being made. And i agree, Karl's delivery is always excellent, clear and concise. Keep up the great work!

[@calebcornwell8473]

This was something I'd been told about the two systems, but seeing it happen is always better. Thanks!

[@kurtb2522]

Enjoyed, learned, as always. Thanks, Karl!!

[@InrangeTv]

Glad to hear it!

[@kurtb2522]

@@InrangeTv This was so good good I had to see it twice twice! Science! Karl, Thank you!!

[@levifontaine8186]

I've been into guns for a few years now and never actually knew how the piston driven ar15 differed from the direct impingement (mine is a regular direct impingement M16 copy). This is fascinating to see.

[@charlesrichardson2372]

This is a great visual experiment of what actually applies to something you hold. Thanks man 🤙🤙

[@floatationdevice2107]

Glad it's back up

[@jeramyw]

Nice. Now how about thermal analysis of AK vs SKS vs VZ58?

[@felixstieger9039]

Yes, please.

[@sirbassist]

theyre all piston driven, so would look the same as the SCAR

[@michaelblacktree]

Karl: Shows thermal imagery of rifles in action Commenters: OMG there's a bird!

[@InrangeTv]

Yeah...:(

[@AlexSDU]

Where? I watch the video again after reading your comment

[@thekraken1173]

@@AlexSDU 1:17

[@AlexSDU]

@@thekraken1173 I saw it. Thanks for the time stamp.

[@thekraken1173]

@@AlexSDU It was 3 years late but glad you saw it.

[@PoundItNailIt]

Perfect video! Thank you for all your efforts! Great education, great stance on all the things! 100% top notch and good form, sir

[@brunoterlingen2203]

Thank you Karl, again a quality presentation, using the KISS system.

[@joehruska8223]

Great short video, answers my questions. Thanks

[@llamabing5215]

This is cool, just having this stuff explained doesnt allways help but actually seeing it leaves an impression

[@ADSaaron]

4:31 *"Whether it was a little short or not"* My man! I look for short videos! The fact that you were able to explain something in less time than most people shows how well you actually understand the concept. This video gets a like from me. *"If you cant explain it simply, you don't understand it well enough"*

[@thomassymonds6308]

Cool Footage! I'm guessing the middle of the Scar Upper is heating up because it's where the barrel bolts to the receiver and the 6-o'clock rail.

[@jacobmichael1911]

I would be interested to see more footage like this, it would be very interesting to see the effects of thermals on other systems as well, such as Blowback systems.

[@lunaticrider209]

I love shooting my scar17s! Whether it’s Steel or brass ammo. On hot summer days or cold rainy days it hasn’t let me down. I can’t wait to put a short barrel on it. Cheers from California!

[@chug2138]

209, yeah Galt! Woot-Woot!

[@lunaticrider209]

CHUG 213 Cheers from the 209 brother!

[@UnclePutte]

It was a fascinating expose.

[@TheChadavis33]

Thank you for this breakdown 🙏

[@Al-lo7sz]

I'd love to see a follow on, suppressing both systems to see what the effects would be. Great vid, thanks!

[@fenaxtv]

Cool video, many thanks 👍

[@paulmossom4725]

More thermal videos please. Interesting stuff!

[@BishezicespiceFAN]

That was exceptional YT video. Thank you..

[@michaciozda7463]

Very interesting, thanks Karl!

[@aqualung.]

Thanks for the interesting video, it’s always neat so see the information visually. I’m seeing noticeable difference in fouling between my AR-15 and BRN-180S. The piston gun’s bolt and carrier are cleaner at 500 rounds than the semi-DI‘s at 50.

[@onelonecelt9168]

Piston guns also keep the bolts and carriers cooler during use, theoretically increasing service life of the action components. On a side note: does the handguard on the BRN-180S heat up noticeably during fire? I am interested in them, but I am leery of the m lok handguard they have on it.

[@theangrychairman]

Amazing stuff!

[@zackcorrell5746]

love these guys

[@bfish9700]

Great video!

[@Maxtcc]

Very Interesting, Thank you.

[@demonocolips]

logically knew this never really thought about this. good short video.

[@redrackham6812]

Nothing wrong with a short video, especially not when it is as educational and informative as this one.

[@ptw1987]

great video

[@reubensandwich9249]

Didn't I watch this already or is there a rip in the matrix.

[@nektonic1]

@@itsfyeo1520 It said H&K SCAR instead of FN

[@aroundthebend721]

Rip in the matrix...I saw this a week after you did.

[@marzcapone9939]

Nice work fellas

[@cannonroberts5129]

Nice explanation

[@BikeGuyFPV]

2:36 main reason they switched the charging handle to the rear was mainly from the artic testing grounds. Due to wearing big gloves in cold conditions, the guys testing out the AR rifles found it difficult to get at the charging handle. Hence, why you find the charging handle on the back of the upper receiver on AR rifles today and not on top of the upper anymore. This can be found in the Eugene Stoner interviews here on YT and he explains exactly that.

[@pichikokis]

Great video

[@InrangeTv]

Thanks!

[@KriegZombie]

Thanks for the intel. I noticed the other day that my Sig 716 wasn't heating up as much as my buddy's AR. Now I know why.

[@DangerasTM]

this is a really cool idea

[@honzabalak3462]

Very nice video.

[@MrZonacat1]

Very interesting!

[@f308gtb1977]

Very cool, thanks!

[@xPaPaxZombiex]

Good Content Homies

[@jacobharris7711]

awesome dude.

[@brainplay8060]

That SCAR looked like it was getting REALLY hot in the block and barrel compared to the Brownells. I would love to see a burnout video like the do over at Iraqveteran8888. The effects of high round counts in a short time. Because let's be honest here. The AR15 if properly lubed, not doing that glove dry myth, will function just fine with 800rnds worth of blowback across the bolt. Cleaning happens between engagements whether its an AR or an AK.

[@davidresetarits5616]

brainplay He did a video about a short-stroke gun, a HK416 i think, and the round count was pretty much the same as with an AR-15, but the handguard didn't got as hot since there is no gas tube running through it.

[@brainplay8060]

@@davidresetarits5616 Where did it fail? I figured the heat would be caught up in the gas block and the gas aperture would probably erode quickly or the block would fail. That's just a lot of heat in one area instead of dispersed across the longer area.

[@alexjordan6371]

You had better hope that cleaning happens lol

[@daningebretsen6784]

Can you do a video like this on sub guns for the difference in open bolt vs closed bolt. And blow back vs other( radially delayed maybe)

[@beforbefore2435]

Thank you for the 7.62x51 information

[@mausercal65]

Very informative

[@christinepearson5788]

Extremely interesting

[@glautreu8431]

More thermal analysis! maybe P7 vs Glock? Idk but this is a cool concept and interesting to watch.

[@MrWarwick15]

Nice! Thanks Karl. Rich

[@jesscollins1]

Neat to see the roadrunner enter the scene just over Carl's right shoulder! (your left side of screen) at timestamp 1:16

[@android61242]

Interesting topic.

[@VashGames]

Very interesting.

[@JanTuts]

Last time I was this early, HK was still making SCAR-17's! :D Jokes aside: interesting video, *did* watch again :)

[@jcoats150]

Thank you.

[@happyundertaker6255]

Enlightening

[@loki98Bp]

0:56 "white is hot and dark is not" I love how that rhymes lol.

[@michaelpawluk6791]

You should do more videos like this

[@abigailvalletta3846]

That BRN-10 looks so good

[@calinsa3880]

I am absolutely not a "gun guy" but i swear i'm getting more info out of these video about engineering design then in my engineering design classes :D

[@deathsicon]

saw a great video to illustrate this point years ago with some piston ar15 style rifle, dumped 3 mags on full auto, dropped the last mag and immediately opened it up and pulled the bcg out and held it with bare hands (no video cuts, was holding the bolt less than 8 seconds after the last shot fired), then challenged the video host (i think it was an old tv show) to do the same with his DI gun

[@timstanton6431]

nice job Karl.

[@InrangeTv]

Thanks!

[@stevegonzales4411]

Nice animation

[@Gunner40Five]

Very interesting video. It seems like the heat is "spread out" more in the DI gun. Like no one spot gets as hot as the piston area in the short stroke gun. I would have been interesting to see what the temps were in the hottest areas of both guns. Keep up the good work in range.

[@zendell37]

Every time I see one of these videos I wonder if this is Karl's back yard. And if so...simply beautiful.

[@JeremiahHartmanPhotography]

Thanks for posting this. got my tax stamp, about to assemble my piston upper sbr

[@wanttohangoutjamesmay9058]

It’s interesting to think about the triad offs of these two systems along with others, whether it be reliably over extended firing or accuracy over longer durations or fire. I,as a viewer would love to see a comparison of the accuracy over sustained fire and as a result of that test see the reliability of these two systems. The way they disperse heat is an engineering marvel and an intentional decision..... but who will win????????

[@NessNik]

That was fun , I like my FN scar 16 & 17 , that said ..my friends AR 15 & 10 run just as reliability at a fraction of the cost .

[@rpk5250]

Interesting video. Are you sitting out in the desert southwest someplace? Looks like west Texas

[@Stout936]

Neat! Are you planning on showing us the rest of the guns? Could make a cool cyberpunk kinda vid out of the footage if you don't see much educational value in it

[@Otuhh]

id like to see more thermals on more guns like the fal, g3 or an Aug.

[@u-wot-n8]

Already watched this on Facebook but have some algorithm food

[@michaeljohnsonbaugh7962]

Unintended comparison, but in the side by side shooting, you can clearly see the ergonomics and recoil mitigation implemented in the Scar platform. The sights on the Ar10 are bouncing considerably more than the Scar. It looks like the difference between shooting 7.62x39 Vs 7.62 NATO. Really makes me want to buy a Scar in the future

[@InrangeTv]

The Ar10 platform is better.

[@michaeljohnsonbaugh7962]

No....no... that’s not true, that’s impossible!

[@iaidokaDVILL]

@KillgoreES From what I understand, the whole SCAR program came about when SF were experiencing issues with their Colt rifles under combat conditions in the Stan, i.e. bolt breaking, barrels overheating. Once Colt addressed and corrected those issues, the SCAR seemed mute.

[@alexjordan6371]

The ar system no likey the sandbox

[@daa3417]

Another point of note is the balance between the two systems. It’s not as pronounced with a rifle designed from the start to be a piston gun but on ‘converted’ ARs like the T91 the change in balance towards the front is majorly noticeable and it takes me a while to compensate when going from a 14.5 AR to my T91 clone.

[@nelsonglover3963]

Really interesting video, any chance of doing it without the handguards too?

[@Spollekop]

Interesting. I would really like to see the bolt face next time around. Too see how much heat transfers to the bolt in both systems.

[@as2ds]

Thanks

[@TheObso1337]

Could you please film a series of thermal videos with different types of AK/handguard setups? I have owned a few AKs and one recurring problem seems to be just how hot they get from shooting. A lot of the handguards that I used have not been up to the task of keeping all that heat away from my hands.

[@burgundypoint]

Do more action types please. Different handguard materials and designs. Heat molestation is really a thing when you shoot a lot. This could get interesting

[@Ompasikom]

I was wondering if IRTV was going to do a video about this topic, ever since I read a gun forum posting saying a DI system doesn't heat up the barrel like a piston system does. :-)

[@Veptis]

Do you got the spec on the thermal camera used here? Can't really tell much but it must be VGA or greater resolution. As reflectivity is an issue, it might even be a cooler MWIR system? There seems to be fixed pattern noise tho, which is more of a microbolometer thing.

[@deltasource56]

Can you do the Ar 180 upper? ( thermal image it)

[@420BulletSponge]

Very cool, this old dog learned a new trick

[@Lomi311]

The predator test

[@defaultusername123]

Just smear mud on it. It’ll still work (maybe).

[@elwayfan01]

@@defaultusername123 icwutudidthar

[@EmilioFAD]

I can't say this was surprising, but I'll stick with semi-DI. Did you get the BRN-10 handguard heat shield liners?

[@themastermason1]

As a left-hander, I prefer pistons over DI because the gas is bled off further from my face. This might not seem like such a problem for most but unless you're able to shoot in a dynamic environment like 2GAC, a gas cloud builds up in your face even in outdoor ranges.

[@alexjordan6371]

Guys who run cans know exactly what you mean

[@PaletoB]

Any footage of the G3, M1a rifle?

[@TeamKhandiKhane]

A question that struck me as I watched the final comparison is if either system cools down faster or if that's just a mater of the materials ability to radiate heat. You'd think more surface area would allow better cooling but theory isn't always practical.

[@foreststeel8842]

Id like to see how a roller locked/delayed system compares

[@emuriddle9364]

I've fired both an AK and a 7.62x39 AR before. There really is a difference in performance. With the 7.62x39 AR being easier to control.

[@MrVanlangen90]

Pheasant at 1:18

[@bunnaydawg2864]

i though the scar was a long stroke gas piston system. what about long stroke vs short stroke? which one will get hotter. akm vs vz58 for example. or svd vs romanian