Patent ID: 7934332

Claim:
A method of forming a forged composite firearm barrel using a hammer forging machine, comprising: providing an inner tube having a first density and a wall thickness, the inner tube defining a bore having a diameter larger than the wall thickness of the inner tube; providing an outer sleeve having a second density less than the first density; inserting the inner tube into the outer tube defining a tube-sleeve assembly having first and second ends, the inner tube having an exterior surface including recessed areas disposed proximate to the first and second ends; loading the tube-sleeve assembly into a hammer forging machine comprising a plurality of diametrically-opposed reciprocating hammers having radially oscillating inward and outward motion; supporting the tube-sleeve assembly on a mandrel inserted through the inner tube; simultaneously rotating and axially advancing the tube-sleeve assembly through the reciprocating hammers from the first end to the second end; repetitiously striking forcibly an outer surface of the sleeve in a radially inward direction with the reciprocating hammers; displacing a portion of the outer sleeve to engage the inner tube progressively in sequence from the first end to the second end as the tube-sleeve assembly passes through the reciprocating hammers, wherein the sleeve is fixedly bonded to the inner tube from end to end including in the recessed areas at the first and second ends of the tube-sleeve assembly to form a composite firearm barrel that resists any relative longitudinal axial movement between and the sleeve and tube when bonded together.