Patent ID: 7823314

Claim:
A firearm having a user-interchangeable barrel, comprising: a tubular receiver having a bolt which reciprocates within the receiver; a tubular barrel bushing press-fitted into the receiver, the bushing having an integral feed ramp independent of a barrel and at least two tubular recesses of differing dimension separated by an edge which presents an internal shoulder surface; at least one interchangeably detachable barrel having an unthreaded proximal end for insertion into the barrel bushing, a chamber at the proximal end, and an external shoulder surface axially spaced from the proximal end configured to abut the internal shoulder surface of the barrel bushing when axially inserted into the tubular recesses of the barrel bushing for assembly without rotation, the chamber having an edge surface configured to directly abut and operably align with the feed ramp when installed; a latch assembly having a spring biased catch member positioned to engage and secure the barrel operably in place in the receiver and barrel bushing without rotation of the barrel and manually displaceable by the user to release the barrel for easy disassembly, thereby allowing easy interchangeability of barrels.