By definition "lapping" includes the use of an abrasive. Fire lapping requires applying an abrasive to the bullet and it will remove material.bigben said:I have heard about fire lapping for a while now and I am wondering how a softer material such as copper will actually lap a harder material such as the gun barrel? even more so without actually putting a lapping compound or some sort of abrasive to cut material away?
I think the Shilen quote makes it pretty clear what break-in is accomplishing.All our stainless steel barrels have been hand lapped as part of their production, as well as any chrome moly barrel we install. Hand lapping a barrel polishes the interior of the barrel and eliminates sharp edges or burrs that could cause jacket deformity. This, in fact, is what you are doing when you break-in a new barrel through firing and cleaning.