Grasshopper, I have taken a few antelopes in both CO and WY. and have rarely taken a shot over 250 yds. You might want to raise your zero point a bit to get the max PBR for a 6" dia. with that .260. I always wear a pair of snakeproof gaiters that snap on for easy removal. Got them at Cabelas. They work fine for kneeling shots and I can remove one for under my ass to avoid the cactii. I didn' t do that at first till I got my butt full of little bristles which took a doc and a nurse half an hour to remove. Not fun, and very embarrassing.

Antelope are very curious and can often be brought in by waving something light colored like a hankerchief or cap. I brought one in to 100 yds. while prairie dog shooting one time. Could have dropped him with a .30-30. Just keep your body out of sight as they avoid humans more than vehicles.

Also be sure to field dress quickly and get the hide off ASAP if it' s warm. They sour very quickly, and they are too tasty to waste. Good binoculars are also very worthwhile. Good luck.