Your views please - had an issue recently with rifle loosing zero after it took a knock. Am thinking of getting a collimeter so that I can check zero before I go out stalking. Appreciate a round down the range is the best way, but often this is not practical to do, as I live i town and driving to my stalking grounds, and don't want to let a shot off just to test things as will spook all the deer.
I have used a collimeter and seems like a useful tool for a) helping with initial zero, but then using as a reference to check that the rifle is still zeroed after travelling, taking a knock, or even with a detacheable scope, just to confrim things have gone back correctly.
There also laser bore sighters - are these any good, or as accurate as a collimeter - strikes me that they are cheap, useful for getting onto a piece of paper, but not much more.