Just picked up a new upper in the 300 blackout. It goes nicely with the 5.56 that came with the rifle.
9.5" 300 Blackout Raven w/improved Match Chamber
Spikes Tactical Compressor SBR-300 BLK / EOTech .300 Blackout Holo Sight
NEA PDW stock on SBR ~ makes sense in 300 blackout
PNW Arms Signature Series .300 Blackout Designated Marksman Rifle. (SSDMR)
.300 BLK cartridges compared with 5.56 and 7.62x39
The 300 Blackout round is incredibly popular. Here's why.
Silenced 300 Blackout SBR with Kryptek camo.
300 Blackout ready for supressor with threaded muzzle device.