For Texas Whitetails I use .270 130Gr. My boys use .260 120Gr and one of the other boys uses .22 hornet at .45gr. All dropem fast with a well placed shot. The .22 is a bit on the small side but for short range well placed shots it get the job done.

.270 150 gr. does plenty enough damage for me. I think 150 is about the perfect bullet for whitetail.