Anyone use these methods to assure barrel concentricity?
Quote from "Secrets of the Houston Warehouse"
"Lapping compound was then smeared on the barrel threads, and by applying outward pull, the barrel was lapped into the action threads for full, positive contact. Virgil pointed out that if this procedure is not accomplished, only one thread or parts of one or several threads may be making contact. Anything less than full thread contact, he underscored, is destructive to finest accuracy.
During the lapping operation, great care was exercised to align the barrel straight with the receiver. Virgil used no mechanical means. He simply used his hands and a delicate degree of feel. He stressed that this step should be done with great moderation. A little lapping here goes a long way.
Part of the reason for lapping-in the barrel and receiver threads is to help center the barrel in the precise middle of the receiver. The superb precision gunsmiths who build benchrest rifles correctly cut the barrel threads slightly loose. While this serves several essential purposes, there is no guarantee that the barrel will center when its run up and tightened. Lapping helps eliminate this uncertainty.
Virgil confessed that lapping would not have been necessary on his rifle if he, Wilbur Cooper and seasoned shooter John Jones had not been tardy in developing an important innovation in the mating of the barrel to the receiver. Too late to benefit Virgil, the three jointly conceived the idea of undercutting a 45-degree slope on the inside edge of the receiver ring, leaving about two-thirds of the receiver shoulder untouched and square. Another 45-degree slope, cut farther inside the receiver (on a Cooper action), terminated at the locking lugs. With the barrel precisely cut to snug up against the two sloped areas, as well as the receiver shoulder, perfect barrel centering became absolute and positive."
Link to full article, it's a good read.....
http://www.angelfire.com/ma3/max357/houston.html
Quote from "Secrets of the Houston Warehouse"
"Lapping compound was then smeared on the barrel threads, and by applying outward pull, the barrel was lapped into the action threads for full, positive contact. Virgil pointed out that if this procedure is not accomplished, only one thread or parts of one or several threads may be making contact. Anything less than full thread contact, he underscored, is destructive to finest accuracy.
During the lapping operation, great care was exercised to align the barrel straight with the receiver. Virgil used no mechanical means. He simply used his hands and a delicate degree of feel. He stressed that this step should be done with great moderation. A little lapping here goes a long way.
Part of the reason for lapping-in the barrel and receiver threads is to help center the barrel in the precise middle of the receiver. The superb precision gunsmiths who build benchrest rifles correctly cut the barrel threads slightly loose. While this serves several essential purposes, there is no guarantee that the barrel will center when its run up and tightened. Lapping helps eliminate this uncertainty.
Virgil confessed that lapping would not have been necessary on his rifle if he, Wilbur Cooper and seasoned shooter John Jones had not been tardy in developing an important innovation in the mating of the barrel to the receiver. Too late to benefit Virgil, the three jointly conceived the idea of undercutting a 45-degree slope on the inside edge of the receiver ring, leaving about two-thirds of the receiver shoulder untouched and square. Another 45-degree slope, cut farther inside the receiver (on a Cooper action), terminated at the locking lugs. With the barrel precisely cut to snug up against the two sloped areas, as well as the receiver shoulder, perfect barrel centering became absolute and positive."
Link to full article, it's a good read.....
http://www.angelfire.com/ma3/max357/houston.html
