Hornady OAL Gauge Modified Cases?

[Deleted member 46119]

I have the tap as well.

Of course but I will repeat, a case fired in your gun is going to be more accurate.

If we were to measure the distance from the "datum" of the case to the "ogive' of the bullet we would be more accurate on distance to the lands than the fired case which is more accurate than the new case.

However, measuring this way would probably require a dedicated measurement device of a type I have never seen.

You have got me going on this thought process. I sure didn't need another project......

Perhaps I will work on it.

Goal: a tool to measure from the "datum" to the "ogive" for improved accuracy in determining the distance to the lands.
Compromise: measure from the "datum" to the tip of the bullet.

When the case shoulder is as far forward as it can go in the chamber and the bullet is as far forward in the throat, the distance from shoulder "datum" to bullet "ogive" should be a repeatable accurate measurement.

It's one of those things that my brain likes working on......

 

[Deleted member 46119]

For belted it shoul be belt
For rimmed it should be the rim.

 

[tbrice23]

Correct.

And as far as engraving the bullet with excess pressure, unless the barrel is new, the lands dull to a degree that a consistent pressure on the bullet yields a consistent measurement.
That's why, on my custom tapped cases. I use next to no neck tension on the case.

 

[rcoody]

Correct.

And as far as engraving the bullet with excess pressure, unless the barrel is new, the lands dull to a degree that a consistent pressure on the bullet yields a consistent measurement.
That's why, on my custom tapped cases. I use next to no neck tension on the case.

and with a new barrel as the throat breaks in that dimension changes pretty quickly

 

[jonthomps]

The modified cases are great and I have SAAMI and custom modified cases. I don't see a huge difference.

 

[An Idahoan]

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