I have one of the old Thompson Center Hawkins muzzleloaders which I had given to on of my boys to use a few yrs back. I thought I would try using it for deer hunting, but when I took it out of the case the inside of the barrel was all rusted out as well as what looked like rust all inside of the nipple. I guess it was never cleaned after the last use. Is there any conceivable way to get this guns barrel in good enough condition to shoot half way decent again? What is the best way to remove the rust? I know there will be some pitting left, but I'm concerned more about just getting the rust out and "defining" what rifleing is left. This rifle was built by me in the early 70's from a kit, and believe me it took a lot of work such as draw filing the barrel and major stock inletting, etc. to get to a finished product. Up until yesterday it was the only gun I ever used for deer hunting.