c. 1790 French fowler with 'Twisted' barrels
La Chasse Au Fusil Gervis Francois Magne’ de Marolles 1789
An Essay On Shooting (An English adaptation of Marolles' original)
http://books.google.com/books?id=-Q0AAAA...ary_s&cad=0The
(Twisted) barrel when forged (is) made to undergo the operation of twisting, which is a process employed by the French workmen on those barrels that are intended to be of a superior quality and price to others; but which as will be seen in the sequel, is very different from that followed by the English workmen in the formation of their twisted barrels. This operation consists in heating the barrel in portions of a few inches at a time, to a high degree of red heat, when one end of it is screwed into a vice, and into the other is introduced a square piece of iron with a handle like an augre and by means of these, the fibres of the heated portion are twisted in a spiral direction that is found to resist the effort of the powder much better than a longitudinal one. To render this operation as complete as possible, it is necessary to observe, that when one the several portions of the barrel have been twisted, the heats that are afterwards given in order to consolidate the fibers of the metal in their spiral direction, by means of the hammer, ought not to be very great. Otherwise the grain of the metal will regain its former state, and the barrel be no better than it was before it underwent to twisting.
From the process it is evident, that to twist a barrel in this manner, throughout its whole length, it must be forged nearly a foot and half longer than it is intended to be when finished, that a portion at each end may be kept cold, so as to give a sufficient purchase to the vise and twisting instrument during the operation: these portions are afterwards to be cut off before the barrel is bored.
The English workmen with whom we have conversed…are all of opinion…that this process of twisting…is really injurious to the barrel, by straining the fibres of metal.
