I ruined 3 different nipple wrenches trying to remove the battered nipples from an original '58 Remington. I had soaked them for some time in various penetrating solutions too. I finally made a nipple wrench from a deep-well socket, made it so it fit TIGHT, as in having to tap it onto the nipple. Then I put it into my 1/4" electric impact driver. That did the trick, backed them all out with no problem. I replaced the nipples with modern made replacements from Lodgewood, along with a bit of anti-seize on the threads. Lodgewood also has a replacement cylinder for the original Remington at a very reasonable price.