It used to be old graybeards would look at my peep sighted rifle, nod approvingly and say to me, "See ya got a Foolproof. Good, good..." Now I am the graybeard saying that to younger folks. There is a great deal to approve of. The windage and elevation settings are finely adjustable. They ride on screw shafts and the setting have countable clicks and a visible index. Adjustments are supposed to be in minutes of angle and fractions, but of course that will vary with the length of the barrel, as a matter of simple geometry. Since I have this sight on a rifle that is longer than normal, and on another one shorter than normal, nothing works out to even units. The adjustments are, though, consistent. Once you have the sight adjusted, you lock the settings into place with set screws and they aren't going anywhere.
Various peep aperture inserts will fit the Williams, including those made for Redfield and Lyman sights. You can also shoot the sight with no insert, which gives you a large hole to sight through with a narrow rim around it, a "ghost ring." I get better accuracy with an insert but shooting without one lets you get a sight picture in low light conditions.
The Foolproof is one of those old products that, like Hoppe's No. 9, caught on a long time ago and never went out of style.
When you add a receiver sight to one of these old fashioned, long-barreled Mausers, you get a tremendous sight radius, which allows for very good shooting indeed. The barrel on this elegant old rifle is 29" long, then there is the length of the receiver in addition to that. The distance between the front sight and the rear sight is about 33 inches!
Using this sight instead of a scope keeps the gun compact, and that is what I want from this little carbine--the clout of an intermediate rifle cartridge in a weapon that's no more trouble to carry than a .22.
There are various situations in which a good iron sight is just the ticket. Some people tend to overlook that. We live in an age of rails and optics. Well and good; I like optics just fine. But sometimes the old answer is still the right one.
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