Each barrel is hand finished before it leaves our factory, this is in the form of hand lapping
Hand lapping is essentially pouring molten lead down the barrel to get a direct negative image of the rifling. We then apply our specially formulated lapping paste to the lead cast, which is moves back and forth along the barrel via a shop made lapping rod. This has two main effects on the rifling, firstly it creates a uniform dimension along the whole barrel or if done correctly, can even put a slight taper towards the muzzle. This taper ensures a perfect gas tight seal around the bullet as it progresses down the barrel, and is most beneficial when using pure lead bullets.
Secondly, hand lapping will increase the surface finish and ensures the lay of the metal is following the direction of bullet travel. This helps in reducing copper build up and maintains better consistency over a longer period of time. It is also a form of quality control, which we can instantly feel from the push and pull of a lapping rod and if there is any errors in the twist and dimension uniformity.