Patent ID: 9459060
Filing Date: 2016-10-04
CPC Classification: F41A,Y10T

Claim Text:
1. A firearm comprising: a lower receiver having an extension portion with an opening, the lower receiver being configured to selectively couple with a first upper receiver having a first barrel and a first bolt carrier assembly, the first upper receiver sized to receive a first bullet having a first caliber and a second upper receiver, having a second barrel and a second bolt carrier assembly, the second upper receiver sized to receive a second bullet having a second caliber, the second caliber being smaller than the first caliber; and, a buffer assembly common to both the first upper receiver and the second upper receiver and disposed at least partially within the opening, the buffer assembly including a biasing member and a buffer member, the buffer member being movable in a range defined by a first position wherein the buffer assembly is compressed by recoil forces and gasses generated by firing of either the first bullet or the second bullet from the firearm, and a second position wherein a first portion of the buffer member extends past the opening towards a forward end of the firearm or a third position wherein a face of the first portion remains flush with the opening, wherein the buffer member is movable between the first position and the second position when the first upper receiver is coupled to the lower receiver and wherein the buffer member is movable between the first position and the third position when the second upper receiver is coupled to the lower receiver.