I'm threading a barrel to fit the square thread 03 A3 pattern. Mocked up some SS stock and cut one, just to ensure that I wouldn't bugger up a good barrel. Seems I've got it right, both in the cutter form (true square) and width. I'm running my "max" barrel thread height at 1.045", and my "max" barrel thread root at 0.998, and my unthreaded portion (pre-thread) at 0.100 long by 0.999" max diameter. Of course, it's a 10 TPI.
Here's the question: when working a square thread cut, when "tweaking it in" to the individual action, how do the pro's "tweak"? As the barrel sits in the lathe right now, it's too tight on the action (good). When I dykem the barrel, I don't seem to be getting good witness marks. Generally, everything gets "touched". I guess that could mean that "everything" is too big. But, if it were you, how would you know to concentrate on either the tops or the roots of the thread form? (bearing in mind that my cutter has been "proofed" as correct, against cerosafe cast of the action thread form)
Here's the question: when working a square thread cut, when "tweaking it in" to the individual action, how do the pro's "tweak"? As the barrel sits in the lathe right now, it's too tight on the action (good). When I dykem the barrel, I don't seem to be getting good witness marks. Generally, everything gets "touched". I guess that could mean that "everything" is too big. But, if it were you, how would you know to concentrate on either the tops or the roots of the thread form? (bearing in mind that my cutter has been "proofed" as correct, against cerosafe cast of the action thread form)
