I just polished my barrel a couple weeks ago using the method listed in the link to the other forum above. Worked well. I haven't patterned my gun after polishing yet but have never heard of patterns getting worse, only better. My 835 shot great patterns before so I'm not hoping for much improvement but it would be niceto see that it made a difference.
Whispering Pines Taxidermy and Turkey Decoys
Mossberg 835 UltiMag Turkey, Indian Creek .720" , TSS 98's, mounted decoys. Double Bull Darkhorse Blind.