With the recent buff to the perk, Subsistence is one of the best PVE perks in the entire game.

Is subsistence good on hand cannons?

tl;dr – Subsistence is good with Auto Rifles but bad with SMGs and Scout Rifles (and likely Hand Cannons and Sidearms – needs testing) ... Runic weaponry is Warhammer Fantasy is always much stronger than even the best normal weapon.

Does subsistence Proc kill clip?

Sub returns ammo from reserves to magazine on kill. 2 bullets per kill. Kill clip needs you to reload. So you can't proc kill clip if you don't need to reload.