I'll be totally honest. I don't see any reason to spend a lot of money on a level. I bought a fist full of them off eBay a while back for $3 a piece. Now you can find them for $5. Yeah they are rough milled. But once you level the rifle and then install the bubble level it serves purpose just fine. Here's a pic I took for a friend describing how I install them. I can look through the scope with my right eye and see the bubble with my left eye. This rifle also has a bubble on the scope mount. I also prefer to mount mine out by the bell of the scope that way my eyes don't have to change focus as much to see it. The closer it is to my face it takes longer to focus on the bubble and then focus back on the reticle and target. With the bubble mounted right up against the scope bell it's almost instant to swap focus.
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