Recently I needed some new scope rings and ended up with the popular Millet Angle-Loc's. These fit Weaver style bases and are windage adjustable. Millet quality is generally considered to be quite good and these appear to confirm that reputation. But I take issue with the Angle-Loc design and feel they could potentially get the casual user into trouble.

When rings are tightened on an expensive scope tube it is extremely important that the holes through the front and rear set of rings be perfectly aligned with each other. If not the valuable scope tube may be severely stressed and the innards damaged. Since these rings are windage adjustable, which means they can be independently moved sideways on the base, damaging your expensive scope is a distinct possibility if you are careless when mounting your scope.

I have long believed that when mounting a scope it was important that the main tube be aligned directly above and parallel to the gun's bore. In recent years, with the advent of more forgiving modern scope mechanisms, it has become common practice to use any old base and ring set that fits and not to worry about this alignment issue so much.

With most fixed ring designs setting on one-piece bases it is usually possible to get away with this kind of quick and sloppy installation. But since both of the Millet Accu-Loc rings are windage adjustable, extreme care should be taken to avoid the possibility of a misaligned ring that could damage the innards of your scope.

One way to avoid this problem is to adjust the opposite sides of the Accu-Loc base mounting screws so that they are both screwed in the same distance when tightened, therefore positioning both rings dead center above your base. I found that if both sides are equally tightened that the screws end up about 1 3/4 turns from being all the way in. By turning the mounting screws all the way in, then backing one side out 1 3/4 turns on both rings, loosening the screws on other side far enough to allow seating the rings on the base, then tightening them entirely from this opposite side, results in a centered condition and avoided the misalignment problem defined above. (That is essentially what I have done for years without a problem. -Ed.)

But these are supposed to be windage adjustable rings, right? Now suppose after you get your scope mounted you then bore sight your rifle and decide to take advantage of this feature to correct any Windage misalignment. You take the provided Allen wrench and screw the rear ring adjustment so as to move that ring sideways the needed amount. Ouch! You have just misaligned the holes through the two rings, possibly stressing your main tube. (Good point, but I've never had a problem with any scope in Millet rings. -Ed.)

Even if you first loosen both sets of scope ring tube screws to allow some room for give, when you tighten them back up after the windage adjustment, the ring to ring hole misalignment problem, and tube stress, will still be there.

In order to safely take advantage of this so-called windage adjustment feature you must always lap your rings after making any adjustment and before tightening them up to correct the resulting scope hole misalignment and avoid stressing that main tube. My observation is that most folks don't have any idea how to lap scope rings, or even if they do, will not take the time to do it.

With any two-piece base set-up the possibility exists that the two separate base pieces are going to be misaligned because of slight errors in the location of the pre-drilled holes in your receiver, and then even more care is warranted. Of course, in that case, the windage adjustable Millet rings can be used to properly align the scope with the bore, and the rings with each other.

The bottom line here is that if you are not clear about the details of correctly mounting a scope, take it to a reputable gunsmith and let him or her do it for you.