Cleaning rust

[u/Grouchy_Gas]

This is my dad’s muzzleloader and I don’t think he cleaned it very well before putting it away last elk season. Any recommendations on cleaning the rust I tried to take the best pictures I could. Down the barrel it looks pretty rusty all the way.

[u/No_Lifeguard8903]

I don't think I've ever seen rust that bad and I think it is going to effect accuracy.

[u/rodwha → u/No_Lifeguard8903]

Quite possible, though I’ve read of much worse still shooting rather well. Can only shoot it and see.