Scope mounting pitfalls

If I try to list all of the possible scope mounting screw-ups I have seen over the years, this will be a very long (and likely very boring) section. Even a very nice scope, if improperly mounted, will not work very well. Pretty much any modern rifle comes set-up for scope mounting in some way. It is either configured with a grooved receiver for proprietary rings (CZ, Tikka and Ruger for example) or drilled and tapped for bases of some sort (just about every other maker). Problems can start with something as simple as the holes in the receiver being slightly misaligned from the factory, which in turn causes the rings to be misaligned thereby putting undue pressure onto the scope tube. Then there are the potential problems with improperly machined rings and bases themselves.

All of that is pretty well known, but I still often see people getting $5 rings for their $500 scopes. If that is not “asking for trouble”, I do not know what is. Reasonably well-made rings and bases can be had for as little as $30-$40 with prices going all the way up to $200-$300 for fancy quick-detachable designs. Whichever version you decide to get, it helps to check and make sure that the rings are concentric (there are kits available for that or a gunsmith can do it for you). Oftentimes, it also helps to epoxy-bed the bases to the receiver. If the rings are not concentric, they should be lapped (once again there are kits available for that). Alternatively, if you do not need a quick-detachable mounting setup, Burris Signature Zee rings have self-aligning plastic inserts that take care of ring alignment problems.

There are quite a few different mounting systems out there and most of them, if properly executed, are equally suitable for most applications. One exception to that is the so-called “universal” or “standard” system that has a dove-tailed front ring and windage-adjustable rear ring. In this set-up, the brunt of the recoil is absorbed by the front ring alone, so I do not recommend this system for hard-kicking rifles.

If you choose to mount the scope yourself (and it is generally not very difficult if you have the right tools), make sure you know the torque specifications for both the rings and the bases. Some manufacturers have that information on their website, while with others you may have to give them a call. This is probably the most common problem I see with scope mounting: overtightened rings. I have seen scope tubes crushed to the point of permanently mangling the scope. In more mild cases, overtightened front ring prevents the side-focus knob from operating properly. Combination of overtightened and mis-aligned rings can cause most scope adjustments to seize-up completely.
Bottom line is that if you plan to mount your scope yourself, pay attention to little details; it can save you all sorts of headache later on.