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Re: Groove diameter

Posted by Wayne McLerran on Wednesday, 13 August 2014, at 11:47 p.m., in response to Re: Groove diameter, posted by Dick Hosmer on Wednesday, 13 August 2014, at 10:50 a.m.

I beg to differ. You can get close but measuring across the corners will generally be off around 0.002" to 0.003". To verify I just measure the groove diameters of two TD Cerrosafe chamber casts made from the same rifle . Measuring across the corners with a high-quality vernier caliper and a standard micrometer the average was 0.4611". The V-anvil micrometer measured 0.4636".

Now, to determine the land heights, measure across one land and the opposite groove with a standard micrometer or vernier caliper. Then subtract the value from the V-anvil measurement. Therefore 0.4636" - 0.4557" equals 0.0079", which is the height of one land.



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