I’ve cleaned the barrel of my BSA Mercury with a bronze brush and a pull-through with oil on it, the rifle suffered the ‘cheese buffer phenomenon’ and there was plenty of this material stuck to the compression cylinder and probably therefore it got in the barrel.

When recrowning the muzzle I did the pushing a pellet through technique. As well as the lip at the muzzle I noticed a few tight spots along the bore, though none of them were VERY tight, just points of resistance. These got less after the above mentioned thorough cleaning, but did not disappear altogether.

I don’t want to ruin the bore so I’m leaving at that. Presumably the lead from the pellets will smooth things out when it’s had a tin through it. Do people burnish they’re bored to get rid of all tight spots? Is it worth it? What are the risks?