I have just a little experience at this. I used some pliers to carefully pull a target bullet (not copper plated) from its case (by wiggling it from side to side), and after making sure that I had thoroughly cleaned and lightly oiled the bore, I inserted the nose of the bullet in the muzzle of the barrel, and tapped it flush with a plastic hammer (there was some shearing off of lead in the process, but it is so soft, that I was not worried about it hurting the crown.), then I started it down the bore with a short piece of dowel followed by a coated rod that I have that has female threads, and coating to the end. I had taken the further precaution of taking a turn or so of blue masking tape around its end, to better center it. From that point I pushed the bullet down the barrel taking some pains to stop short of it coming out of the bore, and cycled it back and forth from muzzle to chamber a few times, slowly, feeling for any changes in resistance. The barrel that I did this is had quite a bit to tell me, none of it good. I was able to improve on it quite a bit, but that is a possible topic for another thread.