I am curious about experiences with dedicated CMMG pattern builds. Mine took a little tweaking to get it where I want it, but it has always eaten about any ammo I load in it.

I bought a few thousand rounds of "tarnished" factory second ammo cheap before the pandemic and its pretty crappy. 2 of my sons and I were shooting 22 LR today - Ruger MKII, Marlin model 60 and Walther P22 all choked hard on the factory seconds. Not the dedicated rimfire AR, it ran through it without a stutter.

That has been a pattern with the gun, it just runs and runs. I am using RTB (CMMG) and Black Dog mags, extra power extractor spring, and a bolt weight but it was as reliable without the springs and weight.

I am very interested to know if I just got lucky, or if the CMMG pattern runs well for other folks.

Andy