Here's a wonderful sight - sold by Brownells and in this case, on my 14 gauge muzzleloading rifle.
: There is also a base for it, that fits round barrels of various sizes. They also have one with only 2 leaves. The leaves are very tall when new, so filing-in is no problem for a modern rifle. I grooved the faces of the sight and put in low temp silver solder vertical lines for low-light indicators for centre. The shallow "V" with a bead front sight is the fastest, most accurate iron sight I've ever used. The rifle pictured shoots 1 1/2" for 5 shots at 100meters off the bench virtually every time. This level of accuracy is difficult to do with "U" or narrow "V" notches - easy with shallow "Express' sights. They are not close range sights only, as some gun writers describe them - but incredibly accurate sights for any rifle. My iron sighted modern rifles also have this shape of rear sight.
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