Patent ID: 8418393

Claim:
A firearm that comprises: a tubular magazine having a longitudinal axis, a forward end, and a first mechanical connection adjacent the forward end; a retaining mechanism arranged in the tubular magazine and having a circumferential surface extending from the forward end of the magazine, the retaining mechanism having a plurality of retaining mechanism locking components arranged on the circumferential surface each of the retaining mechanism locking components extending substantially parallel with the longitudinal axis; and a cap adapted to be received over the first circumferential surface and having a second mechanical connection configured to engage the first mechanical connection to couple the cap to the tubular magazine, the cap further including a plurality of cap locking components arranged along an internal surface of the cap and configured to engage the locking components of the retaining mechanism, wherein the retaining mechanism locking components and the cap locking components are configured to radially engage so as to resist rotation between the cap and the retaining mechanism when the cap is couple to the forward end of the tubular magazine.