https://www.adcofirearms.com/acc/aefit.cfm

PropDoc, I have a few questions regarding the OPS M4-M suppressor and mounting options.  I'm using the RIS II on a .gov profile BCM 14.5" midlength barrel so I'm certain there's enough room to accommodate the collar and allow the can to mount up just forward of the handguard.  There is a very slight step already turned onto the barrel profile from the factory; is this what the OPS collar mounts against or will the end of the barrel require re-profiling?



I'm looking at having ADCO re-profile (if necessary), mount the step and pin the OPS A1 birdcage flash hider, and then move on the M4-M when funds become available.



I'll tag this thread and then send you a PM if you happen to miss my post.  Thanks in advance.

Answered your PM, cause i missed this. Sorry.

 The BCM 14.5" mid, gov't should be good to go. I am pretty sure the step is correct for use with a standard OPS collar (same as step on standard M4 barrel), and should need no modification.

It looks like most of the BCM Gov't profile barrels are slightly tapered right before the muzzle threads.
Would this work, or does it still need re-profiled?
And if it does need re-profiled,  does the gas block need to be removed? If I go with a BCM upper with a DD rail, will the pinned low pro gas block have to be removed and reattached?
12.5"


Im looking at a BCM 12.5" and mounting an M4-M
It looks like the longest rail I could use would be 10"

One more question, will the M4-M or M4-S work with an 11.5" with shaved FSB. After the bayo lug is cut off is there enough room for the collar, or is the FSB too far forward on an 11.5"
Or would you recommend I get the 12.5 and have you cut to 12" or 11.5" and re-thread (to make sure threads are correct) if there is enough room before the fsb?
11.5"