It's official, midlength gas systems are superior to carbine gas systems.

[greentips]

Do know if the pig tail gas tubes increase the dwell time to about the same duration as rifle-length systems? That would be extremely useful in carbines with really short barrels where you cannot use a mid-length.

Pig tail was a regular solution for AR pistols back in the old days. Those are the days when and before the discovery of H buffer and increasing compression in the extractor spring. LMT came up with the enhanced bolt carrier for carbine gas system to try to increase the dwell time. Basically, there are two approaches - Storing more energy in the system to counter the effect of higher port pressure, or trying to mitigate the effect of the port pressure in altering the energy needed to activate the piston.

A large part of the issues back in those days, I suspect is Colt's poor quality control. If colt has better quality, some of the issues of broken bolts might not rear and people probably wouldn't spend as much time on investigating the issue of carbine system....and then SCAR.

 

[Travis Bickle]

Eeverything is inferior to rifle lenght. End of story.

The most accurate statement made on this thread so far.

All the actual information regarding this is very well covered here:

https://www.guntweaks.com/ar-15-reliability-test-cases.html

A lot of what I always took as gospel over the years was quickly dispelled from this article/study and some research after.

 

[cancer]

Rifle length, collapsible butt and a decent sling are really all 99% of us need, no matter what your job is. It isn't broke and it doesn't need fixed.

 

[Gunnerlove]

Gas port erosion. Throat erosion. Higher gas PRESSURES in carbine systems places more STRESS on components, including the barrel and chamber.

I put premium in my car and it got 50% better mileage than my truck gets on regular. This proves that premium fuel gives 50% better mileage.

Failure to even acknowledge the scientific method invalidates testing and effort. This test was a waste of time, ammo and targets. I doubt the person who designed the test dresses themselves most mornings.

 

[DILLIGAF]

Wasted time, money and effort.

Well the keyboard warriors would disagree...lol...

I cant believe this is actually news.

 

[badboybeeson]

Where has eveyone been for the last 15yrs

 

[Moe]

I must be lucky. Been running carbine length on 14.5" and 16" barrels of my own AR's and work C8's (even in the sandbox) for the last 20+ years. Had a failure to feed last November at a pistol/rifle IPSC match. First problem I had in all those years. One carbine I had sold a while back had over 16K on the odometer.

I probably would be better off with mid length but with my track record I'm not losing any sleep.

Flame away
Moe

 

[Moparman1303]

I do notice my bcg slams the buffer hard on my iur c8. It's made a silver circle ring on my H2 buffer but it's smooth not smashing material off. I'm wondering if a h3 buffer would help. Bcg is a full auto lmt.

 

[Twan]

I do notice my bcg slams the buffer hard on my iur c8. It's made a silver circle ring on my H2 buffer but it's smooth not smashing material off. I'm wondering if a h3 buffer would help. Bcg is a full auto lmt.

Can always try! The MRR rifles from factory ship with an H3 - a full auto/semi-auto carrier shouldn't make a difference!

 

[drift1122]

Mid length gas all day!

 

[r34skyline]

I do notice my bcg slams the buffer hard on my iur c8. It's made a silver circle ring on my H2 buffer but it's smooth not smashing material off. I'm wondering if a h3 buffer would help. Bcg is a full auto lmt.

It's normal wear dude. Over time you're gonna get markings on your buffer.

 

[Hilo71]

It's normal wear dude. Over time you're gonna get markings on your buffer.

Exactly. Rifle length, midlength, carbine length, all induce wear on the buffer.