Cleaning an old 91/30
I have an old 91/30 mosin I tried shooting a while ago but it didn't do very well. I wasn't surprised actually because the bore looked really dark and heavily pitted. I considered rebarreling it and went poking around online for an idea of how involved this might be. Wow! Major undertaking, no doubt. But then I came across a reply to a question from someone thinking about the same project and they were advised to try a very thourough cleaning. That's much more within my capabilities,though the technique suggested is one I've never tried . They said to plug the bore at the breach end and fill it all the way up with solvent. Let it sit for a week, then scrub vigourously for a long time. My question for you is what sort of plug materiel should I use that won't leak and won't cause any further damage to the bore. Using a wooden dowel was not advised because it could cause damage. Okay, but this seems odd to me too. The wood is much softer than the metal so I'm wondering where the risk is coming from.
But what I really want to know is what other materiel would be safer to use and that won't leak solvent over the course of a week.
I would be grateful for any advice anyone might have.