05142806 is referenced by 87 patents and cites 3 patents.

A sleeve added to the upper receiver of a firearm for incorporating firearm ancillary equipment. The sleeve has an upper enhancement interface portion and a lower firearm interface portion. The upper enhancement interface portion has standard, universal dimensions regardless of the firearm. The lower firearm interface portion is specific to the particular firearm the sleeve is integrated to.

Title
Universal receiver sleeve
Application Number
7/763966
Publication Number
5142806
Application Date
September 23, 1991
Publication Date
September 1, 1992
Inventor
Richard E Swan
375 West St., W. Bridgewater, 02379
MA, US
Agent
John P McGonagle
IPC
F41G 1/387
F41C 27/00
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