When using a hot bar to reload the sawed-off IZH shotgun after pressing "T" a few times (Which is used for toggling between fire modes) I discovered after shoot 2 slugs at once, that when I used the hot bar the gun would fire (with no sound except for the noise from the projectile and impacts) then play the reload animation, and then fire at the very end. No ammunition was consumed from it except the two shots previous to the reload. I confirmed it was not just visual by testing it on a few infected, and sure enough it does the real damage of the slugs. This process can be repeated by pressing the hotbar fro slugs again, while aiming (which fires where you aim) and then before the animation ends I was able to aim the second shot by pressing space and lowering the gun because at the end of the animation it would raise the gun really quick and shoot straight. This also caused another glitch, which made me walk as if I had a raised weapon when it was lowered, and I ran when the gun was raised, which is unfair for other players who have to keep their guns lowered to move that speed.