I have a hunch that it wouldn't be very durable. I think the solution is better express sights.

I've suffered from poor eyesight all my life, which has gotten dramatically worse in middle age. My presbyopia is severe. For older eyes, I don't think there is any metallic sight that is as easy to use as a true express sight, but there are a lot of really bad fakes out there.

When they begin to have trouble with express sights, most guys assume the problem is the bead. I often shoot DRs that belong to friends and often run across rifles that I lose the front bead on when I try to line up. When that's happened the problem has never been with the bead, it's the rear sight. The rear V should be cut very wide and shallow. For me, a narrow V causes the front bead to fuzz out completely and a larger bead won't help at all. Also, it should be cut hollow enough on the front side to eliminate glare. The centerline below the V should be platinum, never white paint or gold fill. As bad as my eyes are, as long as the rear V is cut right, I have no problem using an .060" bead. Cut wrong, I can't see a .125" bead.

As for the front bead, it also must be cut right. The bead should be flat on the face of the steel stem. To eliminate glare from sidelights, the insert should have no depth to it at all when viewed from the side (in other words, the opposite of those from NECG, which are the worst I've ever used). As for material, nothing beats platinum. Compared to gold and brass beads, a platinum bead glows like a neon sign and is just as sturdy, yet has no greater issues with glare. Ivory is fine for a folding night bead, but is too delicate for a standing day bead.

Also, the fact that a DR has two barrels doesn't make it a shotgun. A .125" day-glo orange Idaho Baking Potato is fine for a bead on a shotty, but is useless on a rifle. I've used those on big doubles, and every shot at 100 yards was a Hail Mary. Anything bigger than .080" or so is just too coarse to be useful. Get the sights tuned up just right and you'll find that plenty big enough. If it isn't, go to a scope.
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