Farrow's military encyclopedia : a dictionary of military knowledge . of soft or mild steel preparedby the Siemens-Martin process, this metal hav-ing been found to be of a very imiform nature. Thebarrel bars or molds are obtained by contract inlengths of 15 inches, the diameter for rifle bars be-ing li inch. The barrel bar is heated to a whiteheat and passed through the barrel rolling-mill,?which consists of ten pairs of rolls arranged alter-nately horizontally and vertically, when it is drawnout in one heat to the full length recpiired (about 36inches), taper in form, and solid. It is next pa
Farrow's military encyclopedia : a dictionary of military knowledge . of soft or mild steel preparedby the Siemens-Martin process, this metal hav-ing been found to be of a very imiform nature. Thebarrel bars or molds are obtained by contract inlengths of 15 inches, the diameter for rifle bars be-ing li inch. The barrel bar is heated to a whiteheat and passed through the barrel rolling-mill,?which consists of ten pairs of rolls arranged alter-nately horizontally and vertically, when it is drawnout in one heat to the full length recpiired (about 36inches), taper in form, and solid. It is next passedto the Ryder forgins; nuichine, where the • Knox form is forged on the breech end and the barrelcut to length, then passed through a Htraijjhteningmuchine, Ixamined for straightiiess, and viewed a«finished forged. The ends of the barrel are clamp-milled for size and length, anrl then ilrilled up aboutli inch at each end, the diamelerof the holes drilli-dbeing inch. This operation is called enter-ing the bore, and is very carefully tested to uce that. The Fit,. 1, the starting of the bore is true and correct,barrels are now ready for drilling. The barrels while being drilled are placed verti-cally in a machine. Fig. 1. where they revolve witha speed of 300 revolutions per minute,the holes al-ready made at each end acting as guides for the setof three drills used in this operation. The methodof using these drills insures a long hole of small di-ameter being drilled perfectly true, and until thismethod was tried and adopted this was found tobe a most difticidt task: The ilrills consist of, first, the core-drill, for roughly cutting away the met-al. This is run in half an inch, when the barrel istaken out and emptied of swarf or cuttings by plac-ing it (Her a jet-pipe,wlien a strong stream of wash-ing liquor thoroughly clears out the bore. Anotherhalf inch is drilled in the same manner,and the boreagain washed out. The second drill or half-round bitis now used. This dr
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Keywords: ., bookcentury1800, bookdecade188, booksubjectmilitaryartandscience
