The metal of the peep in the picture is 1/8" thick, I made one from 1/16" metal but like the thicker metal better.
A lot of people have suggested that I put a second attachment screw in the sight to hold it in place, with the deep countersink and a tight tang bolt mounting it is stable. This sight is just a temp, I am closing in on the time that I will need have cataract surgery at which point I will no longer need it. Because of this I don't want to drill another hole in any of the tangs of the guns I mount these sights on.
This peep sight is for hunting, I really have it torqued down to hold it in place it doesn't move easily. I set it up and adjusted it to have the front blade perfectly centered in the rear sight notch and even with the top of the rear sight for a 6 o'clock hold, if it should shift I can easily tap it back into alignment.
Here is the peep sight that I made out of 1/16" metal. It is Ok but I like the thicker metal better, this one has a little give (spring) to it, the thicker metal is rock solid.
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