There is no comparison between .300 BLK and .223 when it comes to short barrels. The .300 has considerably more muzzle energy and retains it's performance better with a pistol barrel.
Not to mention you can suppress it and run subsonic rounds (if your state allows), so you won't blow your windows out from the concussive blast of a 5.56.
The downsides are more drop and lost energy at long distance, and expensive ammo if you don't reload. Even the cheapest rounds are still 15.00/20. I can reload them for ~30 cents per round, and it's even cheaper if you buy components in large quantities.
Hi-Point carbines make a fun truck gun/plinker for not much money, and 9mm is even cheaper to shoot than 5.56.
Not to mention you can suppress it and run subsonic rounds (if your state allows), so you won't blow your windows out from the concussive blast of a 5.56.
The downsides are more drop and lost energy at long distance, and expensive ammo if you don't reload. Even the cheapest rounds are still 15.00/20. I can reload them for ~30 cents per round, and it's even cheaper if you buy components in large quantities.
Hi-Point carbines make a fun truck gun/plinker for not much money, and 9mm is even cheaper to shoot than 5.56.
