So my son (60lbs) is going to WY for antelope this fall for his first big game animal. He'll be shooting a 243 Win loaded for youth shooter, something around 75-80 grains doing 2700-2800 fps. He is coming along nicely and progressing well with some smaller bullets, but a fully loaded 90g bullet makes him uncomfortable and his accuracy suffers. I've looked at all of the major manufacturers but don't want to be shooting varmint bullets because of too much expansion, but I'm afraid that bullet expansion will suffer on their big game offerings due to the lower velocities of a longer shot. Question is can anyone recommend a ~80g bullet that will do the job on an antelope out to about 300 yards?