greydog,
I have seen the results of some of the problems you mention through my borescope more than once.
Eventually my friend caved and let the gunsmith do the job, which included setting the barrel back a couple threads to totally clean up the old chamber. The rifle never shot worth a darn again. I would guess the factory chamber job was well-done, because the rifle shot so well, but do know the rechamber wasn't, because I got to look at it through my bore-scope: The rifling was obviously much longer on one side of the throat than the other. (I reported this off-center rechamber job in an article years ago, and the magazine got a nasty letter from a reader, saying it was impossible for a chamber to be off-center, due to the pilot on the reamer.)
But have also seen the same thing, a number of times, in the throats of various factory rifles. The really interesting part is sometimes they still shoot pretty well!
John,
I have also witnessed the off-center chambering on at least four barrels, as seen through my borescope. I never knew how it happened, but rifling would start on one side of the barrel way before it would be evident on the opposite side.
On one new Remington barrel, it caused Remington factory .308 ammo to give high pressure signs immediately. As you noted, the gun shot acceptably well in spite of it. A new custom barrel took care of the problem. Don't know if Remington would have done anything about it.
Borescopes are fascinating devices. Sometimes they reveal some sloppy problems. And sometimes they ruin perfectly good rifles!
WyoM70
