Patent ID: 7789009

Claim:
A mounting system configured to couple an auxiliary device to a firearm having a barrel defining a longitudinal axis and a fixture coaxially secured to the barrel, the fixture including a forward surface, a rear surface, and a pair of flat surfaces 180 degrees opposed to each other adjacent the rear surface, the mounting system comprising: a rear cap including an internal bore extending from a rear end to a forward end, the forward end including a first locking thread, the rear end including an opening in communication with the internal bore and having a concentric opening portion sized to receive the barrel and centered along the longitudinal axis, and an eccentric opening portion along one side of the concentric opening portion and sized to receive the fixture, the rear end also including a pair of locking surfaces and a rear seating surface adjacent the concentric opening portion and opposing the eccentric opening portion; and a mount extending rearwardly from the auxiliary device and inserted into the internal bore of the rear cap through the forward end of the rear cap, the mount including a forward seating surface configured to engage the forward surface of the fixture, a second locking thread configured to mate with the first locking thread of the rear cap, and a rear portion configured to seat within the internal bore between the fixture and the rear cap, wherein the rear cap is axially slidable with respect to the mount between a first position wherein the first locking thread and second locking thread are adjacent for engagement, and a second position wherein the rear portion of the mount is disposed adjacent to the forward end of the rear cap, wherein the mounting system couples the auxiliary device to the firearm by (i) sliding the rear cap to the second position with respect to the mount, (ii) inserting the fixture into the rear cap through the eccentric opening portion, (iii) moving the pair of locking surfaces and the rear seating surface of the rear cap into respective engagement with the pair of flat surfaces and the rear surface of the fixture, thereby positioning the barrel of the firearm in the concentric opening portion, (iv) sliding the rear cap to the first position with respect to the mount such that the forward seating surface of the mount engages the forward surface of the fixture, and (v) rotating the rear cap with respect to the mount along the longitudinal axis to threadably engage the first locking thread and the second locking thread, wherein the respective engagements of the forward surface and the rear surface of the fixture with the forward seating surface of the mount and the rear seating surface of the rear cap prevent longitudinal movement of the auxiliary device with respect to the fixture and the barrel, and the engagement of the pair of flat surfaces of the fixture and the pair of locking surfaces of the rear cap prevents rotational movement of the auxiliary device with respect to the fixture and the barrel.