Heavy Barrel has no effect on shotguns As a test it would be interesting to see Heavy Barrel get the added benefit of reducing shotgun spread, now that Improved Rifling murders TTK -10 / 20 / 30% Accuracy loss -5 / 10 / 15% Shotgun pellet spread  ( a far cry from the DOW's 35% ) -5 / 10 / 15% weapon damage It'd prioritize aiming properly since you need to make up the damage loss by hitting more pellets, and their CQC effectiveness will also be reduced, as tighter spread = need better aim =