A great explanation of how tilt affects a shot.








Glad I have been installing bubble levels lately plus the importance of mounting your scope.

Thanks for the link. I’ve seen a number of statements about the importance of leveling a scope, but no detailed discussion like that.

What’s usually ignored is the effect of not having the center of the reticle plumb with the bore. I admit I’ll have to view and consider the explanation of that effect, but it does seem just from what isn’t discussed that it doesn’t matter much. When I started thinking about the question some time ago my first thought was that it would be difficult to ensure the center of the reticle was in the plumb line center of the bore. For example, even if the receiver of the rifle could be leveled with an integral mounting rail or other feature and then the reticle was level, how would be know that the center of the reticle wasn’t offset left or right of the center of the bore?

What I've noticed is every optic I've mounted needed some windage from mechanical zero, which supports your theory that optics don't naturally line up with the bore of the barrel. On one bolt gun I use a Redfield mount, which allows you to correct for the scope being off bore and allowing yu to actually start with an optic zeroed with no windage dialed in either way.