Two make that three things that relate to this discussion: At actual sanctioned benchrest matches, watching experienced shooters, I have see a lot of junk rod guides and really bad rod technique. Secondly, I have talked to an experienced button rifle barrel maker who is an artist at lapping, and I don't want to misquote him, but it takes a lot of cycles of a cast lead lap, charged with the appropriate abrasive to enlarge the groove diameter of a barrel .0001 inch, more than you might imagine.
This is
exactly,
my experience as I have lapped my own barrels with very improved results and found it takes about an hour to make any appreciable difference with the desired results evenly throughout the whole length of the bore.
And yes, just to change internal dimensions even .0001" may even take 2 hours
and this is with diamond compound, not silicon carbide which breaks down too fast into smaller pieces
and is why I don't believe most hand lapped barrels are worth their advertising
as I don't believe most barrel makers take even a half hour of proper handlapping with a lead lap
100 strokes minimum, maybe 200, before progressing to the next size finer grit
casting a new lap for each different sized finer grit.
It is something you want to sneak up on like machining to a fine tight tolerance
Not something you want to hurry up and hog out a bunch of material.
So it is slow and tedious
Almost worth just buying a new barrel lol
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Your button rifle barrel maker knows his stuff
Who is it if I may ask? because I'm impressed he's not lazy just wanting to get it done quick
and knows how to do it right
and upon reading your post I may try one of his barrels considering he knows the correct methods
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One reason I choose Krieger is through my independent research I read the Military spec'd out 18 Micron for their lapping and Krieger takes it down to 32 micron which is about 600 grit