I have a Zeiss 4.5x14 Has 64 MOA updown. Going on top of 270 WSM w/26" bbl. I think I can get a 130 grain bullet to 3300 f/s, maybe 3400 with the long bbl. I have not yet graduated to true, long range shooting, but decided to set things up so that I could at least shoot a little longer range if desired. I have purchased Burris signature bases with a full set of inserts so I can adjust the cant of the bases. Using a combination of inserts, the Burris setup can go from 5 moa to 30 moa cant. The question is how much. I read a lot about the importance of optical center. So that argues for no more cant than is absolutely necessary. I looked at the balistic tables for my load. Wow, beyond about 500 yards it gets pretty nasty. No wonder you fellas trend toward cannons... My drop at 500 yards is about 34 inches. At 600 it 55. Seems like to do me any good at all I'd need to put a full 20 or even 25 MOA cant in the bases. How much is that going to effect my optical performance when I shoot at close range though? Presumeing I keep a 100 yard zero and shoot at a deer at 100 yards, the scope would be at the very bottom of its adjustments. Totally outside of its optical center. Appreciate your thoughts -- I intend to sight it this weekend and hope to cinch down the mounts and forget about them.