Normally if you find a shredded patch or blown patch I suggest going to a thicker patch. This is not the case with you. It sounds like you have a ruff bore. The bore is engaging the patch on the way out and as it spins tearing it apart.

First thing I would try is putting a wonderwad under the patch between the powder and the patch and ball and see if the patch comes out perfect. I have shot patches and could have and have reused them they were in that pristine condition. This is normally only possible when you use a bore button.

If that does not help and the patches are still being blown, then I would get some J-B Bore Paste and a piece of Scotch Brite Pad and shine the ruff spots out of the bore. This is not lapping mine you, this is just taking the ruffspots out of the bore.

I should ask, is the accuracy good? If it is, then don't worry about it unless that really bothers you. Also is the rifle new? Many times, new rifles are ruff in the bore and over time and lots of shooting will smooth themselves out and that problem will disappear.