Also, you're never going to be shooting from a vice so theres not much point in achieving such a perfect zero. Your only gonna shoot as good as your skill. The military zeros weapons wearing all our crap, off a sandbag, rushed by naggy safety officer, usually in less then ideal weather conditions and still nail that 300m target. My suggestion is set up, get your zero, then practice as much as possible until you know your skill level inside and out. I'm more impressed by someone who can use a little dope and nail that sweet long range shot then with someones uber tight 100m shot group. just my 0.02$