OAL Question

[JEC]

A buddy and I both used the same reamer ....in ... different action types and the OAL cartridge lengths are about .050 differnt to touch the lands. How is this difference explained?

 

[John Kielly]

I could easily understand that barrels with different manufacture or rifling might cause minor differences in OAL, likewise different projectile batches or manufacture. Beyond that, my best guess would be that you two have measured your jump differently & are loading to that, unless you are jamming, in which case go back to the first option.

 

[4Mesh]

Did one of you chamber a barrel with a lot of rounds down it? If there was no rifling to speak of, that would explain why the throats were so different.

Did you both use a set of go/no go gages?

What is a shoulder dimension on a fired case from each rifle? Are they off by 50?

 

[JerrySharrett]

A buddy and I both used the same reamer ....in ... different action types and the OAL cartridge lengths are about .050 differnt to touch the lands. How is this difference explained?

Measure the fired cases at the shoulder using something like a Stoney Point gage then go from there. (Now Hornady Lock-n-load)

http://www.midwayusa.com/ebrowse.ex...egoryString=9315+***+651+***+682+***+8868+***

This set is nice to have for all rifle reloading. Get items #1 and #2.

Item #1 allows you to measure the bullet position at the ogive/body intersection which is a much more accurate measure than measuring the bullet point.

Item #2 allows you to measure the case at the shoulder. Many shooters use the #2 to set the sizing die for shoulder setback. I prefer using a stripped bolt for this operation, but you are looking for differences, not chamber fit.

 

[karls42]

Bet you are using different bullets.
Long thin VLD type bullets will be seated much further out to touch than a fatter blunt hunting type. OAL is the wrong way to measure rifling contact.
Did you use a seperate throater?? That starts a whole new set of problems.