I just got and used a Wheeler Level-Level-Level from Cabela's. One piece mounts by a magnet across the bolt raceways, the other you set on top of the vertical turret adjustment (NOT on the turret cap, apparently)... turns out both rifles had the crosshairs WAY off... you're dealing with such a fine piece of wire that a little (seemingly) can be as much as 6".
Now having said that, it looks like both scopes are canted when I hold the stock (seemingly) vertically. I'm hoping and guessing that this is because of how I've been holding the rifle, and that with the level being used, the crosshairs should be or are actually plumb to the bore.
Can anybody verify this for me?
BTW, the Wheeler setup was only $25 bucks. If it works, and Wheeler anything should, it's a heckuva deal.