I bought a little coach gun (Marstar) and noticed after shooting it there was a black build-up at the end of one barrel. After cleaning it I discovered that the build-up was caused by a coating of silver solder at the end of one barrel. When the barrels were silver soldered together there was a small imperfection in one barrel where the silver solder entered and sweated around the barrel. This rough surface is trapping debris. I will only be shooting shot so do you think this is a problem.


















































