It seems the big question with bolt sleeve sights is Do they return to to the same position each time the bolt closes? The answer is Yes. The Belding & Mull has a flat spring that rides on the tang as the bolt closes; the Howe Whelen, Goss, Marbles Goss, Hart and Niedner bolt sleeve sights have adjustable pins and or screws that rest on the the tang when bolt is closed. Even the two home shop-built bolt sleeve sights in my collection have addressed this problem. The next problem mentioned in this thread is How fragile is the windage screw on the Lyman 48? The answer is Very, very! Griffen & Howe solved this problem which can be seen in the below pictured sight.
Gary Bush
