07131228 is referenced by 143 patents and cites 33 patents.

An M-4 firearm having a lower receiver assembly and an upper receiver assembly. The upper receiver assembly is connected to the lower receiver assembly. The lower receiver assembly has a fire control assembly. The upper receiver assembly has a barrel and a hand guard. The hand guard has a venting features for allowing cooling air to pass therethrough. The hand guard has a heat shield mounted therein. The hand guard has at least one peripheral device mounting rail. The hand guard has an upper portion and a removable lower portion. The removable lower portion has at least one peripheral device mounting rail. The removable lower portion may be removed and replaced with a different second removable lower portion without the removal of fasteners.

Title
Modular firearm
Application Number
11/154738
Publication Number
7131228 (B2)
Application Date
June 16, 2005
Publication Date
November 7, 2006
Inventor
Arthur F Daigle
Plymouth
CT, US
Laurance Robbins
Plainville
CT, US
Paul Hochstrate
Plantsville
CT, US
Agent
Perman & Green
Assignee
Colt Defense
CT, US
IPC
F41A 21/00
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