[Blitzkrieg]

Sounds like you need some copper solvent run through that bore.. and yes I then use Breakfree or synthetic motor oil afterwards to protect the bore in storage..

 

[Blitzkrieg]

It's also a good idea to always inspect a stored or fielded bore before shooting.. things like spiders can and have crawled in and built a sturdy web with a few victims packed in. Would hate to be behind the gun firing the first round. Better safe than sorry