Sound like you might be using 777 it does that. There have been cases where it was a real problem. There are several ways of helping the situation one is to use Blackhorn 209 powder, some that use 777 move there breach plug every few shots. You do need to put a good anti-seize or teflon tape on the plug after cleaning and do NOT crank it down tight finger tight is the rule. If you are using 777 then do try the Teflon tape it is the best answer for 777. You might also us the search engine and look up the thread on applying it by Sabot loader. Lee