11.5" build, calling on those with experience

[Pappabear]

Many different options, just like cars, will work. LMT enhanced BCG, is great. But for what your looking for its hard to beat RGP 11.5 barrel from Sionics. Go with A5 buffer set up, for sure.

PB

[slowrx]

I have currently one, and have had as many as 3 BCM 11.5 uppers. All ran suppressed/un-supressed with a factory gas block, carbine buffer spring and either an h1/h2 buffer. I also have a BA 11.3 hansen profile barrel that I run with a bootleg adjustable bcg that runs great as well.

[jackblack73]

My softest shooting gun is a suppressed 11.5" BCM with standard lightweight barrel (not ELW). Whenever friends shoot it they can't believe how smooth it is. It's 100% reliable suppressed and unsuppressed, with absolutely nothing special done to it. No adjustable gas block, and standard carbine spring with an H2. I've tried a Sprinco blue but can't remember why I switched back. My can is a Silencerco Omega. I think shooting .223/5.56 out of a .30 caliber can also adds to the smoothness and lack of back pressure.

[Biggy]

As others have said, if you have the bucks, the easy way to have probably the best one *overall* at this point in time, is to just buy a KAC 11.5”.

[themonk]

My softest shooting gun is a BCM 11.5 elw upper with an A5H3 and a gemtech ajustable bolt carrier.

[crossgun]

Just know and I understand the why you want to run both with and without the can that you will be over gassed when suppressed. The gas port in both my 11.5 BCM barrels pins at .073 and I have been trying to smooth it out. With a BCM gas block, BCM BCG and H2 buffer and standard spring the rifle ran great with and without. I recently switched to the A5 tube with a LARB buffer which really smoothed it out and reduced the recoil impulse.

Running with an adjustable gas block set for my Omega by far has made the biggest difference and has me realizing that I cant have the best of both worlds.

[gunnerblue]

I have two 11.5” carbines, both with Sionics barrels- one is the RGP that is run mostly suppressed it functions perfectly without a can as well. The other is the ERGP with a dedicated SOCCOM556-RC that, somewhat surprising, also cycles unsuppressed with .223-pressure ammo (Federal XM223SP1) though will not always lock back on empty. Both carbines use Colt BCG’s and Vltor A5H2 buffers with standard springs. The only thing I would change is perhaps to try LMT enhanced carriers in one or both.

Both run very smooth and are well-balanced with a KMR-A rail and Geissele SMR (respectively) and Magpul SL stocks. I primarily shoot the RGP with Saker556k but occasionally with an Omega (both in Key-Mo mounts), no issues with either.