It sounds like the +3.5 is to high for your rifle. You will want a shorter sight to center your shots in the bull at 100yds. I would suggest that you buy the +1, +1.25 and +2 sights to see which would work best, or you can always just file the +3.5 you have. I'm thinking the +1.25 should work, but it would be good to have several to try.