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US 4,622,080 AGranted
Gun barrel, mandrel and related processes
AssigneeAmerican Metal-Tech, Ltd.
InventorWolfgang Wegwerth
Life of this patent
Estimating the term…
Abstract
A gun barrel which is either smooth or has lands and grooves wherein the grooves are both wider and deeper at the chamber than at the muzzle. A mandrel for producing the gun barrel. Processes for producing the gun barrel including steps of heating, quenching, and tempering with optional use of chromizing, vacuum, and noble gases.
Claims24
A process for producing a gun barrel comprising the steps of:
- I. inserting a mandrel into a tube having an inside diameter greater than the outside diameter of the mandrel;
- and then
- II. collapsing the tube radially inwardly to mechanically deform the tube until the inside of the tube takes the form of the outside of mandrel;
- and then
- III. removing the mandrel from the tube;
- and then
- IV. heating the tube to a temperature above the recrystallization temperature to the metal but below the melting point of the metal;
- and then
- V. quenching the tube;
- and then
- VI. tempering the tube to produce a gun barrel having an inside diameter of greater than 20 mm.
8 more elements
A process for producing a rifled barrel having an inside diameter of at least 20 mm comprising the steps:
- I. inserting a mandrel into a metal tube, wherein the mandrel comprises:
- A. a shaft for moving the mandrel longitudinally with respect to the inside of the tube;
- and
- B. a cylindrical portion attached to the shaft having mandrel lands which produce grooves in the tube and have mandrel grooves which produce lands in the tube;
- wherein that portion of the mandrel adjacent to the shaft has mandrel lands which are 0.1 to 0.6 mm wider than the same mandrel land remotest from the shaft;
- wherein that portion of the mandrel adjacent to the shaft has mandrel lands which are 0.1 to 0.6 mm deeper than the same mandrel land remotest from the shaft;
- wherein the mandrel has an outside diameter less than the inside diameter of the tube;
- wherein the mandel has a length less than one-half that of the tube;
- wherein that portion of the mandrel remotest from the shaft is aligned with the muzzle of the tube;
- wherein the metal is ductile, cold-formable and heat-treatable;
- and
- wherein the metal contains the following elements which are present in the indicated range of weight percent:
- ______________________________________ Element Range of Weight Percent ______________________________________ C 0.25 to 0.80 Si 0.20 to 0.80 Mn 0.50 to 1.00 Cr 0.50 to 4.00 Mo 0 to 2.00 Ni 0 to 0.50 V 0 to 0.50 Cu 0 to 0.20 P 0 to 0.07 S 0 to 0.07 Fe balance essentially;
- ______________________________________
- and then
- II. collapsing the tube radially inwardly by radially hammering the metal to the tube at the muzzle of the tube until the transverse area of the tube has been reduced by 30 to 40 percent and until the inside wall of the tube contacts the mandrel and fills the mandrel grooves forming barrel lands;
- and
- III. moving the mandrel slowly toward the breech of the tube while moving the point of hammering to keep it always over the mandrel but at the muzzle end of the mandrel when the mandrel is near the muzzle and at the breech end of the mandrel when the mandrel is near the breech;
- and then
- IV. removing the mandrel from the tube;
- and then
- V. filling the tube with argon at a temperature of 20.degree. C. and at a pressure of 760 mmHg;
- and then
- VI. sealing the muzzle and the breech of the tube;
- and then
- VII. heating the tube to a temperature 10.degree. to 100.degree. C. above AC.sub.3 for two to sixty minutes;
- and then
- VIII. quenching the tube by reducing its temperature from that of the proceding step to a temperature less than 120.degree. C. in an elapsed time of less than one minute by immersing the tube in cold water;
- and then
- IX. heating the tube to 500.degree. to 900.degree. C. for one to two hours in order to temper the metal of the tube;
- and then
- X. lowering the temperature of the tube to room temperature;
- and then
- XI. opening the muzzle and the breech of the tube whereupon the resultant tube is termed a rifled barrel.
31 more elements
A process of producing a gun barrel comprising the steps of:
- I. inserting a mandrel into a tube, said mandrel comprising:
- A. a shaft for causing relative movement between the mandrel and the inside of the tube, and
- B. a cylindrical portion attached to the shaft having mandrel lands which produce grooves in the tube and having mandrel grooves which produce lands in the tube,
- wherein that portion of the mandrel adjacent to the shaft has mandrel lands which are both wider and deeper than the same mandrel lands remotest from the shaft, and
- wherein the mandrel has an outside diameter less than the inside diameter of the tube;
- and then
- II. collapsing the tube radially inwardly to mechanically deform the tube until the inside of the tube takes the form of the outside of the mandrel;
- and then
- III. removing the mandrel from the tube;
- and then
- IV. heating the tube to a temperature above the recrystallization temperature of the metal but below the melting point of the metal;
- and then
- V. quenching the tube;
- and then
- VI. tempering the tube to produce a gun barrel.
12 more elements
Dependencies are inferred from the claim text.