Do you need to remove a barrel jacket bushing on a Remington Model 81?  Here is a quick and cheap way to make your own removal tool. Grab an old 3/4″ shallow socket. Anneal the socket so its soft enough to cut. ( Make sure you let it cool slowly!)   Place the socket into your mills vise. Remove material so  you are left with 2 pieces on opposite sides.  I made mine .080 high by .080 wide and it worked great.   Your tool should line up with the notch cuts in the bushing. Now just find a ratchet and begin unscrewing to start your disassembly.