300 black that just works - supers and subs - Daniel Defense DDM4 300 S, URG, 10.3in, 300 AAC Blackout Complete Upper Receiver w/ Flash Hider

This is a great deal. This is a very high-quality DD SOCOM-MK18 upper chambered in 300 Blackout. A MK 18 retails from DD for $2,200. The math is simple: pair this with a very high quality lower and use the savings to buy ammo.

It is heavy because of the pic rails on top, bottom, left and right, but that doesn't bother me. The bird cage flash hider works well, but let's be honest you're going to be shooting this suppressed. And the really good news is that, in my experience, range and match supers and subs cycle fine with a suppressor. I haven't had to make a change to the buffer assembly and haven't had to consider an adjustable gas block. It just works.