CMMG PCC Upper

[TacticalG34Tupperware]

Does anyone have any experience running the CMMG 16in upper for PCC, I really like the idea of being able to run my 3-gun lower and getting solid practice in with the exact setup I run for multigun. Also do you guys think the 30 round mags would be a heavy hindrance to being competitive?  

[Joedirt199]

I just built and ran a cheap cmmg upper with parts I had on hand. Went with the 8.5" barrel and a taccom barrel extension for full 16" length. 30 round endo mags ran perfect and have seen too many people struggle with their homemade builds on dedicated lowers with stick and glock mags that are extended. Now just playing with buffer weight.  Currently have standard AR buffer but have one of each weight up to try and see if the recoil is better. Holosun 510 green dot for optic.

[StealthyBlagga]

You can start that way if you wish, though you will be doing more reloads. If you get more serious, you can get yourself a dedicated 9mm lower later. CMMG Guard is a great system.

[nikdanja]

Only a side I see is the actual round. Less recoil but being able to use your 3g lower is pretty sweet.  

[Chillburger]

Has anyone had luck with various buffers with the CMMG RDB system? I have a factory 8in that I've been using for some of the club PCC matches around me, and I've been toying with the idea of trying a Blitzkrieg 9mm buffer with a Vltor A5 buffer tube. This is based on some comments from arfcom threads.

[Joedirt199]

I tried a H buffer and it helped. Ejection was more forward but still fine. Settled the dot down some.

[mrd]

Many people seem to prefer their CMMG RDB short stroked with a Blitzkrieg/Kynshot 5005 buffer and 308 carbine spring, preferably JP polished, running 135-140 PF ammo. Optimal setup might vary, depending on your load and barrel length.

 

I run my 16" CMMG short stroked with a Kynshot 5004 buffer, which is slightly shorter, weight is pretty much the same as 5005. The 5005 was out of stock when I ordered. My setup gives a little more pre-load on the spring. No idea what is better, 5005 or 5004, I haven't compared them. It's night and day compared to a bone-stock CMMG 16", though! Softer recoil and much less dot movement.

Edited November 12, 2019 by mrd
added info

[Chillburger]

I just ordered a 5005 and a few JP springs to mess around with. Thank you for the suggestions!