Developed as an alternative to the 5.56mm round for the US Special Forces, the .300 Blackout cartridge is designed to give the benefits of the heavier, larger caliber .30 round, but allow for the performance of A 9mm  submachinegun when fired through a suppressed, short barreled rifle (SBR.) Most importantly, the Blackout cartridge does not require modification of the bolt, unlike the 6.5 Grendel or 6.8 SPC. The .300 Blackout round hasn’t been adopted as of yet, but is starting to find popularity with civilian shooters looking for a more powerful AR-style rifle.

M4 SBR .300 Blackout

PM: 0   S/R: 2/10   AMMO: 30   DC: F/H   CLOS: 0-12   LONG: 40-70   CON: +3   JAM: 98+   DR: -2   RL: 2   COST: $1800

GM Information: Without a silencer, the SBR has a DC: of G/I. In a standard 16″ barrel carbine M4, the .300 Blackout has the same stats as the M16 from the Q Manual, except for the DC: J/L and ranges of CLOS: 0-15   LONG: 50-80.