AR 15 SBR Choices and Decisions

[ptmccain]

I made the mistake of handling a friend's SBR (11.5 BCM Upper) and really loved it.

Now, my question is this and I'll what I'd want it to do and what my budget is.

I'm a big fan of Daniel Defense and their MK18 10.5 barreled upper is of interest to me, but I've read mixed reports on its reliability and I have read BCM's explanation of why they think an 11.5 barrel is the better way to go for overall more reliable gas operation/performance.

I should mention that while I'm not planning, for now, to get a suppressor, I'd like to buy something that would allow for that in the future.

Also, I have access to full auto lowers I am allowed to use, so I'd want that consideration to be in the mix here.

My budget is around $2,000 max.

I'd welcome any thoughts you guys might like to offer on what you feel is the best choice in SBR upper and why.

[markm]

10.5 will run fine if gassed right. 10.5 unreliability is 90s thinking. People used to run those with carbean buffers and hot ammo, and lo and behold the shit didn't run.

Now we know that you can't just dump an .080" port on the barrel and expect it to run. And with a lo pro adjustable gas block, you can make a 10.5 really sing.

[trauma]

This is the SBR I bought
https://www.youtube.com/watch?v=Ar0UOJbMfDU

[ptmccain]

OK, that's good to know....what 10.5" upper do you feel is the best out of the box at this point?

[Renegade04]

I run a LMT 10.5" upper on mine. It works just great. The LMT is also a fantastic choice if you plan on a suppressor later on.

[markm]

OK, that's good to know....what 10.5" upper do you feel is the best out of the box at this point?

Fixed FSB would be an LMT probably. Lo Pro gas block? I don't know.

[midSCarolina]

Don't know if I'll catch flak for this around here but my favorite may be the LMT MRP 12.5" .... piston

Other than I would go with what Renegade04 posted... maybe accessorized in a slightly different manner but for all intents and purposes, that.

[MistWolf]

For a shorty upper that will see high volume shooting, it's probably best to get one that's chrome lined with a 5.56 chamber. I'd also give serious thought to an M4 type profile barrel because of heat. Getting gas flow right is very important so I suggest getting a good adjustable gas block as chances are very good that you'll get a suppressor at some point.

I haven't tried the LMT Enhanced carrier yet, but the experiences of folks like Grant show it's a noticeable improvement over the standard carrier. I'm running a rifle RE assembly on my shorty AR and it's better at taming recoil than the pistol RE using a carbine H2 buffer. I think using the A5 assembly on an SBR is the way to go.

With what we know today, I think a 10.5 upper is very doable. Mine runs great, even on a full auto lower and although it has less than two hundred rounds through it, it's enough to uncover anything obvious. When I can afford to, I'll be adding an adjustable gas block.

There's a lot of good info in this thread- https://www.m4carbine.net/showthread...essed-SBR-Ever

[albatrossarmament]

My LMT 10.5 has been utterly reliable. I bought it after shooting my brother's LMT 10.5 that is also utterly reliable. Both suppressed and unsuppressed.

[docsherm]

My wife has a LMT 10.5 that runs great. No issues at all with a regular LMT BCG.