J
J. Valentine
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Thankyou Jerry Sharrett for taking the time and effort to tell members how you chamber.
Thankyou Jerry Sharrett for taking the time and effort to tell members how you chamber.
Ideally, you would do all this indicating on an unturned barrel blank, and when all the chamber work and muzzle work was done, then the barrel could be contoured between centers and get both chamber and muzzle back into the same plane...........
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Hi Roy,
Actually, it is not the cutting of the chamber and muzzle in Gordys method that would potentially set the muzzle off center to the stock alignment with a wandering barrel bore, but the cutting of the threads and shoulder in the same setup as the chamber cut which are the key elements in determining position.
No amount of re-contouring between centers after the thread and shoulder have been cut, will bring the barrel back into alignment.
My chambering method and results are almost identical to Gordys except for slight variations in the use of range rods, which is strictly an ease of setup variation.............Don
gordy said:But don't stop there, now keep moving the indicator forward past the throat up the bore a ways ahead of the chamber. Depending on how much curvature that particular barrel has, you will IMMEDIATELY start to see some bore runout. Sometimes this shows up quite well in as little as 1/4" to 1/2" into the bore ahead of the throat. Long bullets aren't even clear out of the case yet and they are having to turn ever so slightly to get lined up to the bore when they are starting into it.
Wrong Gordy my friend. The wanderings of a gun drill does not make a continuous curve. I call that curve a "compound curve" from my old highway surveying days but I'm not really correct there either. A compound curve is a curve where the radius is continually changing. In the barrel bore situation there is a 3-dimensional wandering.gordy said:The whole length of the bore is a continuous curve from one end to the other, some more so than others. But the amount of curvature in 2-3 inches of most bores is almost not detectable if that part of the bore is running true to the centerline of the lathe, and it is much more easily detectable when dialing in both ends of the bore.
From here on out it is just a pi$$ing contest.