As others have said, the problem isn't with the nipple or breachplug. It's with the bolt. Sabotloader has developed an alternative to Remington's version and it shows a lot of promise.

Check out these threads:

http://huntingnet.com/forum/black-po...00ml-farm.html

http://huntingnet.com/forum/black-po...converson.html

http://huntingnet.com/forum/black-po...-700-farm.html

http://www.huntingnet.com/forum/blac...onversion.html