I know I'll probably get flamed for this, but I really want help


I was working with the AR models trying to give the AK-47 the recoil and RoF of the M4A1. I was trying a few different things and after no success I noticed for the AK files, there are: PVMLA_AK-47, PVMLA_W_AK-47, and PVMSH_AK-47.
What are the differences in PVMLA and PVMSH; and PVMLA and PVMLA_W?

Sorry if I've wasted anyones time by being a choob!