I've used Federal Power Shok (the cheap stuff) 150's in my M14 and M1, no problems. Plastic tipped bullets are reccomended by some (Fulton Armory etc), as lead tipped bullets may have particles of lead peel off them and get into the action; in theory. Keeping your rifle clean should solve this potential problem however. I haven't had problems with softpoints myself, but when I went out to get stocked up on bullets for reloading, I did actually get plastic tipped Hornady SST's (165's) and Nosler Accubonds (165's).