It was not until ISSO that the first really modern guns were commenced in the United States (by both navy and army), and com mencement of regular manufacture was several years later. The establishment of the Army thin Factory in Iss9 may be regarded as the final c•o11mitment of the United Mates govern ment to the built-up forged-steel system. hi ls!to the United States Navy had 6-inch.
and la-inch modern built-up guns in service; the army 3.2-inch guns and ]'_'-inch mortars; both opervices had types of all calibres under test. 31eanwhile elaborate c•,Ilcu]at]ons were being made in Europe, and reliable working formulas for the shrinkage deduced. By 1550 the system may be said to have been quite fully elaborated. Krupp in Armstrong in England, and Italy. the French. and others were then regularly turning out excellent built-up guns.
Iln:-Wocall GUNS. III 1872 Dr. Wood bridge's design for a ]0-inch !nuzzle-loading rifle made of a thin tithe wrapped with wire brazed together IT immersion in melted bronze was inneh recommended. The gun after 93 rounds was torn apart longitmlinally by the force of discharge. It was evident that brazing could lie\ lir be relied upon for longitudinal strength. Two other 10-inch gulls upon the Wood bridge design were recommended in I5S1 to be made and tried. One of east iron with breech wrapped with wire was abandoned before com pletion. The second consisted of a steel tube the full length of the gun, the rear half being slat-minded by longitudinal bars of steel, and the whole wrapped with Ace] wire at high ten shin, decreasing toward the exterior. The pres sure upon the breech was transmitted through bars to the trunnions.
The Crozier wire-wound gun. commenced in 1889. consisted of a forged-steel tube wrapped over its whole length with tinned square steel wire and incased by east-steel jacket and hoops, the jacket carrying the breech block and trun nions. All circumferential strength was to be obtained from the tube and wire. The tube was first wound at such tension as to compress it beyond its elastic limit and thus give it a special elastic limit. then WI won,nd and wound again with the designed tension. The who was coutiunonsfv wound, the ends of the pieces as manufactured being electro-welded.
The first Brown segmental tube wire-wound gun was of 5 inch calibre, and bail a very thin tube of high elastic-limit steel extending only from the breech to a short distance forward of the seat of the projectile. and forming a mere lining for the main tube, which was of Lmgiludimif steel bars the length of the gun. This was wire-wrapped throughout with such high tension that even when powder pressure acts the tube is under compression. This is to prevent the joints from opening, but necessitates the tube I>eing initially com pressed beyond its elastic limit, which is not desirable. in the latest development of the Brown system, not as yet fully tried. the seg mental bars are replaced by thin plates radially .and bent into epieyeloidal forms by the wire winding. They extend from the breech to the muzzle, and are designed to give lotiritmlal strength and same tangential resistance from their frictional hold upon each other. A steel jacket connects the trunnions to the breech block.