I think 4X12 is okay for antelope. From my experience, 3-400 yrds is a close shot on them in southern NM. I used to hunt them in the early 70"s with a Rem 1903A3 .243 with a Weaver K-10 or Win 70 .30-06 with a B&L 2X8. Leupold and Burris probably make the best scopes for what they cost now.
You will like the 700BDL. I have one in .22-250 with heavy barrel for target/varmit.