Barrel rust removal from a rifle

[Sky Zero]

Originally Posted by rolandtg

I cleaned a buddies M44 Mosin using long stainless wire brushes I got a Harbor Freight.
They sell them several in a package.
He had fired some ancient corrosive ammo and then then just chucked the rifle in the closet.
It was really sad. I tried conventional cleaning methods and finally resorted to the wire brushes.
It took quite a while but I got the barrel cleaned up pretty well. It was still pitted, but clean.

Do you remember what sized brushes? Mine is also the mosin, so whatever you used will work for me. Thanks!