I have used them for the last two years and have shot eight deer with them I shoot A winchester APEX with 150gr 777 and it makes quite A mess when recovering bullets there is not anything left of them I shoot the 245gr .50 cal It works ok but you dont get much penitration I have not had A pass through yet. I would have A little concern about shooting A large buck with them. This year I am going to try the spitfire MZ An all copper bullet that is supposed to retain 100% of its weight. These are made by Barnes. Has any body used these bullets yet how did they work