I've often wondered - so now I'll ask your thoughts...
I set up and machine meticulously enough so that my chamber has no more than 2 tenths runout when done. I am told Clay Spencer guarantees 1/2 a tenth. I'm wondering, though, does it make any real difference? I used to measure every powder charge on an Itin precision lab scale - guaranteed accurate to .05 grains. On the suggestion of a board memeber, I did a test where I simply threw the charges using a Harrell's Culver (using a very consistent throw technique) and my groups didn't change. So, in the end, the accuracy afforded by the scale didn't make any practical difference. I think the same may be true in the chamber. 50 millionths? The case walls of the brass aren't true to that level! I haven't tried this, but I suspect a chamber cut to .00005" runout and one cut to .0005 will not show any difference downrange.
Thoughts?
I set up and machine meticulously enough so that my chamber has no more than 2 tenths runout when done. I am told Clay Spencer guarantees 1/2 a tenth. I'm wondering, though, does it make any real difference? I used to measure every powder charge on an Itin precision lab scale - guaranteed accurate to .05 grains. On the suggestion of a board memeber, I did a test where I simply threw the charges using a Harrell's Culver (using a very consistent throw technique) and my groups didn't change. So, in the end, the accuracy afforded by the scale didn't make any practical difference. I think the same may be true in the chamber. 50 millionths? The case walls of the brass aren't true to that level! I haven't tried this, but I suspect a chamber cut to .00005" runout and one cut to .0005 will not show any difference downrange.
Thoughts?