05343650 is referenced by 147 patents and cites 6 patents.

An extended rigid interface frame with upper and lower rails joined to a firearm receiver and extending forward above the firearm's barrel to a head assembly replacing the firearm's normal front sight. A weaver type interface return portion is provided below the barrel from the head assembly to the receiver. A yoke braces the extended rigid frame receiver sleeve of the present invention to the forward portion of the firearm's receiver. The distal end of the extended rigid frame receiver sleeve terminates in the front sight housing which connects the upper and lower rails and provides a housing for advanced laser and sensor components, and the standard front sight bead. The front sight housing is self supported by the connection of the upper and lower rails running back to the yoke and secured to the top of the receiver. The barrel of the rifle is free floating in that it does not touch the extended rigid frame receiver sleeve in any manner. Protective spring-loaded hand guards are incorporated into the extended rigid frame receiver sleeve, thereby protecting a user's hands from a hot barrel, eliminating any pressure on the barrel, and providing quick access to the barrel area.

Title
Extended rigid frame receiver sleeve
Application Number
7/859958
Publication Number
5343650
Application Date
March 30, 1992
Publication Date
September 6, 1994
Inventor
Richard E Swan
375 West St., W. Bridgewater, 02379
MA, US
Agent
John P McGonagle
IPC
F41G 1/00
F41G 1/387
View Original Source