Re: Concentricity oddites
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: DM.Oakes</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: YAOG</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: DM.Oakes</div><div class="ubbcode-body">A point of clarification. The only thing I'm using the Hornady tool for is post bullet seating/concentricity checking. The Sinclair tool is being used post resizing/neck turning and post bullet seating. </div></div>
O.K. So let's think about what operation(s) do they disagree on.
Please realize that these tools take different measurements from a loaded round due to the way they were designed.
The Hornady gauge measures bullet concentricity relative to bullet tip and case head. This is the wobble in the middle of the bullet of the loaded round using an imaginary axis from bullet tip to base of the case. The Hornady gauge cannot tell you if the measured wobble is on the same axis as the rifle's chamber and barrel only how much wobble it sees. In other words the Hornady gauge can tell you how much wobble there is in the bullet on an axis between the bullet tip and base but NOT if that axis is on the same axis as the chamber and barrel bore.
In contrast the Sinclair gauge measures bullet tip and body concentricity relative to the case axis which corresponds very well with the rifle chamber and barrel bore axis. This is the wobble at the tip of the loaded round and the wobble in the middle of the loaded round. By using the sized and loaded case OD to define the where the axis of the bullet should be relative to the chamber and case the Sinclair gauge gives you information useful for setting up your work process and dies to yield chamber and barrel bore concentric ammunition.
The Sinclair gauge also gives you useful information about your cases but your post was about bullet runout.</div></div>
YAOG - Thank you for this information. I'm just trying to keep myself from getting frustrated in this process. I think I'll just stick to my newly acquired Sinclair gauge and sell/toss out the Hornady gauge.</div></div>
Just because I can't figure out exactly how to use the information the Hornady gauge provides to improve finished ammo doesn't mean it isn't useful. So I wouldn't toss it out quite yet, Hornady is not a bunch of dummies and this information must be useful in some way. I just do not know how it is useful for how I think about building precision ammunition.
HTH!
