Originally Posted By windham:
Ok just took delivery of a PSA 7" 556 Marauder PA15 AR 15 pistol. After much research have decided to swap out the original upper minus the BCG and CH for a 300 Black out.
First will the original BCG and CH work in a 300 bO upper from PSA? What length would you get for a good home defense gun. What grain bullets would you use. Thanks alot.
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a) yes the BCG/CH will work for .300BLK
b) You can reuse the magpul handguards if you use a 8" .300BLK pistol barrel, low profile gas block, pistol gas tube, and regular handguard endcap. Honestly, you can probably reuse your 5.56 gas block and pistol tube if they're not pinned. Technically you probably need a .700-.730 diameter endcap, but .750 has minimal play and it's easier than buying a .625 and opening up the hole to .700-.730
Good price:
8" 300BLK Barrel $118Aero Pistol Gas Tube $12Low Pro Gas Block $18.750 Round Handguard Cap $4c) Pretty much any 8"+ .300blk is going to be solid for HD.
d) Just about any of the 110gr ballistic tip will work great for HD. TAC-TX, Saber, Varmageddon, V-Max, Sig, etc...
Avoid pretty much anything 145-155gr (ie: .308 projectiles loaded into .300blk cases) except as cheap range blasting ammo because .300BLK won't get them going fast enough to do .308-things. They're just going to icepick through targets.
The ~200+ gr subsonics are fun, but unless you're shooting the $$ exotic controlled-expansion things they won't be too good for defense. You're pretty much just lobbing big pistol rounds at that point that, at best, are going to tumble through a target with none of the hydrostatic effects of a 2000+fps projectile. But they are damn quiet and, unlike a pistol or PCC, those long skinny bullets keep decent velocity for a LONG ways... If you can cope with the dope, .300blk subs are good to 200-250+ yards.