hey eyewinder, I had a buddy shoot a few goats with 150 gr 30-06 last year and it worked great. Didnt seem to much and knocked them right down. If you are concerned about it being to much i believe winchester makes 125 and i think 135 gr ammo that would work great for goats as well. Antelope have hollow fur on them which makes them harder to penetrate as well and that is why you can get by with a little heavier bullet. as for where it would hit, you would have to shoot a few rounds through your gun to find out for sure but i wouldnt think it would hit much different then a 150 gr just a little higher because of the lighter load.