High velocity ammunition system and firearm
A round of high velocity ammunition contained within a modified chamber of a conventional firearm has a cartridge case, a sabot mounted within the forward-end of the case and a carrying projectile matching the caliber of the firearm for engaging rifling in the firearm bore, and a quantity of a propellant charge sufficient to impart a muzzle velocity in excess of 25,000 (ft./sec.) to the projectile. The cartridge case and the projectile cooperate with a rearwardly facing abutment surface of the chamber to confine the sabot which has an forwardly facing bearing surface coaxially surrounding a portion of the projectile and in abutting engagement with the abutment surface. When the round is fired substantially instantaneous dynamic forces generated by the gases of explosion propel the projectile from the chamber into and through the bore while simultaneously comprising the sabot to a fracture point. The fragmented sabot is entrained in the gases of explosion and escapes from the firearm through the muzzle end of the barrel.
1 . The combination comprising; a firearm, and a cartridge disposed in firing position within said firearm, said firearm having a generally cylindrical axially extending bore including a breech end and a forward or muzzle end, and a cylindrically stepped cartridge chamber in coaxial communication with said breech end, said chamber including a front portion having a diameter substantially equal to the diameter of said bore, a rear portion having a diameter substantially larger than the diameter of said front portion and a generally rearwardly facing annular abutment surface forming a transition between said front and rear portions for complimentary abutting engagement with a bearing surface on an associated cartridge received in a firing position within said chamber, said cartridge having a cylindrical case slideably received within said rear portion and including a mouth opening at its forward end and a base forming a closure for its rear end, a sabot received within said mouth and supported within said case, said sabot having a forwardly open projectile receiving bore an annular forwardly facing surface coaxially surrounding said projectile receiving bore and comprising said bearing surface, a projectile received and supported within said projectile receiving bore and extending for some distance into said forward portion, and a quantity of explosive propellant contained within said case rearward of said sabot for propelling said projectile out of said chamber and into and through said bore and for fracturing and fragmenting said sabot within said chamber and propelling the fragments of said sabot from said chamber into and through said bore and discharging said fragments at said muzzle end when said cartridge is fired.
2 . The combination set forth in claim 1 wherein said abutment surface and said bearing surface comprise opposing radially disposed surfaces.
3 . The combination set forth in claim 1 wherein said abutment surface comprises a generally conical rearwardly diverging surface centered on the axis of said chamber.
4 . The combination set forth in claim 3 wherein said at least one bearing surface is defined by a conical surface of revolution centered on the axis of said cartridge.
5 . The combination as set forth in claim 1 wherein said sabot is partially defined by a plurality of circumaxially spaced apart and axially forwardly projecting petals.
6 . The combination set forth in claim 1 wherein said sabot has a plurality of distinct barring surfaces thereon.
7 . The combination as set forth in claim 6 wherein said sabot is partially defined by a plurality of distinct axially forwardly extending petals and each of said petals defines in associated one of said distinct bearing surfaces.
8 . The combination set forth in claim 1 wherein said projectile has a generally cylindrical rear portion received in press fit within said projectile receiving bore.
9 . The combination set forth in claim 8 wherein said sabot is received and retained in press fit within said case.
10 . The combination as set forth in claim 9 wherein said case is crimped radially inwardly at said mouth opening to further retain said sabot in said case.
11 . The combination set forth in claim 1 wherein said projectile has an ogival forward portion forming a transition with a generally cylindrical trailing portion.
12 . The combination set forth in claim 1 wherein said projectile receiving bore is a stepped bore including a rear portion, a front portion having a diameter larger than the diameter of said rear portion and a radially disposed and forwardly facing shoulder forming a transition between said front and rear portions.
13 . The combination as set forth in claim 12 wherein said stepped bore comprises a blind bore and said sabot has a generally rearwardly facing end wall forming a closure for the rear end of said projectile receiving bore.
14 . The combination as set forth in claim 13 wherein said rear wall has a generally radially disposed rear surface.