B4 this happens, go to Lowes tool dept, on the lubrication endcap you'll find Dupont spray (dry version) Teflon.
Spray a little down the bore from the chamber end, Be SURE
not to get any in the chamber. Use the little red tube.Run a patch or 3 down the bore from chamber to muzzle. (Not the other way)
This thin coating gets in the pores of the barrel and makes almost impossible for lead to stick.
As a small benefit your loads will be slightly faster. In my experience this trick is good for at least 200 rounds, I've not had a BBL with a leading problem yet.
CWS