USGI M231 & Colt 601 Tool
This video demonstrates the proper method for removing and installing early Colt 601 receiver extensions, which lack standard wrench flats. It highlights the use of a specialized USGI M231 tool, explaining how it interfaces with a hole in the receiver extension to provide leverage. The instructor emphasizes the importance of using the correct tool to avoid damaging these collectible parts, contrasting it with less effective methods like strap wrenches or filing flats.












