Re: Paul Curtis comment on cross bolting 1934 Archived Message
Posted by SGT on September 23, 2008, 10:00 pm, in reply to "Re: Paul Curtis comment on cross bolting 1934" |
I am not aware of any patent infringement on Brown's patent for the rotary bolt; there could be a claim filed somewhere, but I suspect patent protection had expired before Fox and Stevens utilized the design (I believe that patent protection extends 7 years; so with a patent date was 1886, the Fox and Stevens guns produced after 1900 should have been safe from such claim). Personally I am only a novice on gun mechanics; but gunsmith Buck Hamlin tells me that double guns are more prone to wear at the hinge pin than at the bolt joint due to the fact that the steels used for gun bolting had been hardened to a much greater degree that that used in the hinge pin. Dan LeFever recognized this fact very early and used a very ingenious ball and socket hinge design in his Lefever gun; the "ball" being threaded into the frame with an adjusting screw slot so that a slight turn of the screw would put the barrels back on face, effectively tightening the joint to "as new" condition. This design still works as well today as it did when invented; but for some reason has never been copied by another company. Smith guns with the rotary bolt do wear, and will wear faster if the bolt is allowed to "slam shut" when the gun is closed. The late Russ Ruppell was a firm beliver that the proper way to close a Smith gun was to hold the opening lever in the open position until the barrels were closed; then slowly release the opening lever which method allows the bolt to engage with less, but still sufficient force. Another great method to reduce wear to a Smith gun is proper lubrication. Double guns reqire very little lubrication except in areas of wear; on a Smith gun these areas are the hinge pin, knuckle, and bolt. When I clean my Smith I always take care to apply a thin coat of a high grade gun grease to the hinge pin, the hook on the barrel lug, the knuckle of the frame where contact is made with the fore iron, and the areas engaged by the rotary bolt on the rib extension. The Winchester Model 21 is a fine shotgun and was made of higher grade steels than the vintage guns made prior to WWI; they will withstand a lot of use, but still wear loose eventually. I've never studied the Model 21, as I considered them too "modern" to be a vintage gun; and also found them esthetically unappealing. I wish you well as you begin your own research into these interesting relics from American history.
|
|