I think it's pretty good as is but it could be interesting with perks like vorpal, kinetic tremors, attrition orbs, and deconstruction.
Also kills with paracausal rounds should fully refill the mag.
mostly QoL changes, but I think it should do a bit more damage against Bosses and Mini-Bosses.
It's a little too punishing with basically not allowing you to miss heads or stow on the final shot, and the bonus damage does stack up to +1736%, but that hardly matters when Malfeasance, ToM, Quicksilver, and arguably a few others have it beat in general utility and deal pretty good burst and sustained damage as well. Not to mention other HCs with Lucky Pants, which grants up to +600% damage and far better ease of use, as you only need to cause damage