I've hunted with my M1A but never killed anything with it. I used a 180 gr bullet which is too heavy for the M1A because of stressing the op rod. Not wanting to risk damage to my gun I simply turned off the gas valve. The rifle can shoot anything then without damage but will not cycle semi-auto. It must be manually cycled but is ok because it functions like a straight pull bolt action then.
Remember to get a 5 round Mag for it!