What exactly is Firelappin for?
I read recently about a firelapping kit and I assume it is used to polish the barrel. However, I have no idea when you would use it, nor what the results would be. Could someone just sort of run thru exactly why you would use it? And does it take the edges off the rifling?
Thanks Qajaq
What exactly is Firelappin for?
I bought one of the LBT "kits", for a S&W Model 24-3 that had a tight spot in the bore (where it screwed into the frame) and a rough forcing cone.
The firelapping kit basically consists of a small container of lapping compound (fluid + grit), and a pair of lapping plates that areboth hardened and polished. Using a medium-soft cast bullet, roll the bullet between the plates with an excess of the compound. This produces a bullet with abrasive bands - rough to the touch, but not too much so.
The kit's instructions recommend loading these into cases with a light charge of powder, making sure to check for a barrel obstruction after every round.
I followed the instructions to the letter and 'lo & behold, the tight spot in the barrel literally went away, with no visible "rounding" of the rifling. However, the abrasive compound neatly and brightly polished the entrance to the forcing cone - JUST ON ONE SIDE !!!!
I then boxed up the gun and sent it back to S&W for a factory repair to correct the timing / alignment.
I am certain that the LBT folks know what they are doing and the firelapping is a viable process, if their instructions are followed. My revolver was too screwed up to fix with firelapping only.
I hope this is usable information.
Thanks, carelesslove