BCM 11.5" Carbine vs 14.5" Midlength - Supressed

[COJeff]

Been torn between a BCM 11.5" Carbine or 14.5" Mid-length.
Aside from ballistics and accuracy, will a 11.5" carbine have any noticeable less gas blow back when compared to a 14.5" mid-length when either are suppressed?

Will a 14.5" mid-length have less carbon/gunk build up on the bolt when either are suppressed?

How much noticeable gas port erosion will occur on a 11.5" carbine vs a 14.5" mid-length when either are suppressed?

Thanks

[C-grunt]

Outside of the gas port errosion, every one of those scenarios comes down to "it depends". The 11.5 will probably have more gas port wear due to higher port pressures.

Gas port size, ammo used, and can use are all going to change the equation. However, all being equal, the two are going to be pretty close for gas blow back and carbon. Outside of laboratory testing, i don't know if you could really see a meaningful difference.

I can say though that my duty 11.5 DD with a Huxwrx can has significantly less gas bow back and carbon than my 16 inch midlength with my YHM traditional design can.

[markm]

Outside of the gas port errosion, every one of those scenarios comes down to "it depends".

This. Depends on the can, ammo, port sizes, etc. Generally, the longer the barrel the better. Port erosion is a non-issue in my opinion. The throat is where erosion will kill a barrel.

If going 14.5, BCMs ports are leaner at .076" and make for good suppressor hosts. Cans just suck on ARs, my suppressors are paper weights in my safe. I don't even run them anymore.

[joedirt199]

You can control the gas. Nothing says you have to be stuck with a factory gas port. I have been switching out adjustable gas blocks for the old BRT vented set screws in standard gas blocks to choke down the amount of gas when suppressed. My suppressors are permanent and not moving around so no need tune unsuppressed. They run cleaner and less recoil due to the lighter buffers and stock springs. Next to no gas in the face.

I have one carbine 11.5, midlength 12.5, 14.5 and 16" and an intermediate 18". All the longer barrels run YHM TurboKs and the shorter ones YHM Turbo3s. When tuned they all run about the same. Less port pop as well when less gas is needed to open the action.