300 blk

Both of these are supressed. Both are firing 145-150 grain projectiles. Both are subsonic. Both are AR platform PCC or SBR configurations. Bottom line, AR platform, short barrels (let's say equal lengths +/- 1"). Both have the same lights affixed. Both weigh roughly the same unloaded within...

I'd like an AR-15 rifle. Many reasons, but I like the performance of 5.56 out a 14-16 inch barrel, and 300 BLK out of a 7-11 inch barrel. Would it be viable to build a AR-15 as a pistol in 300 BLK with a 10.5 inch barrel and pistol brace, and also run a 14.5 inch threaded barrel with a removable...