User:Supercavitation/M143 SBAIC

The M143 Short Barrelled Anti Infantry Cannon was a last resort, tank-mounted, anti infantry weapon that fired M667 HECS. It was originally designed to replace anti infantry machine guns on tanks, but this was found to be wasteful, as most situations required a few bullets, not a tank shell, and it was relegated to the position of a final anti infantry defense layer.

Design
The was essentially a massive shotgun. It was a large tube, 120mm in diameter, and 985mm long, with a rotating drum behind it. It fired M667 HECS Canister Shells, which made it extremely effective against infantry, however, ammo was large, and it could only hold 10 rounds at a time. It was eventually modified to be used as a last resort weapon, and carried only one shell instead of the drum. It was used if the main turret and or the machine gun had run out of ammo, or neither turret was able to rotate to aim at the target.