Brass trim question. Fire formed, lengths all over the place

[Jed Eckert]

Howdy,
It's newer savage .30-06
RCBS precision mic shows chamber to be SAAMI minimum
Sinclair chamber length tester shows brass can be 2.5" and be safe
Manual says max should be 2.494", trim to 2.484"

fire formed Winchester brass is all over the place. Mouths not square/tilted. Length, is 2.5 to Waaay less. Do I trim them all to be the same? Even if it's pretty short?
Not sure what do.
thanks in advance.

 

[Edd]

I can tell you what I would do. I would set my trimmer to 2.484" and let the shorter and crooked ones be shorter and crooked.

 

[Frog4aday]

What @Edd says ^^^

 

[Jed Eckert]

Well that settles it
Thanks!

 

[thatguyshm]

Personally, I would trim to a thousandth under the minimum to square them all up and then work to a consistent 2.490"ish length. It will help resist a carbon ring from forming, you know your maximum case length, and it will be 0.010" away for tolerances. No need to be any under that.

Take it for what is worth, good luck and shoot straight.

 

[Jed Eckert]

Personally, I would trim to a thousandth under the minimum to square them all up and then work to a consistent 2.490"ish length. It will help resist a carbon ring from forming, you know your maximum case length, and it will be 0.010" away for tolerances. No need to be any under that.

Take it for what is worth, good luck and shoot straight.

I see
I would like to do that but most are shorter than 2.490
Do I leave them be till they grow after firing/ full length resizing?

 

[thatguyshm]

How short is the shortest in your batch?

 

[Jed Eckert]

2.4775"

 

[thatguyshm]

Personally I'd run it all down to 2.477 to square up case mouths then check back after a few firings. They won't all grow the same, and it will take quite some time to reach 2.490".

 

[L.Sherm]

I would trim to 2.484 and you can sort out the shorter ones if you want. Stay after the carbon ring and you'll be fine. If you shoot the shorter ones they'll grow and eventually get to 2.484

 

[Edd]

2.4775"

If it will give you a warm fuzzy feeling, trim them all until they are squared up. The SAAMI spec for a 30-06 case length is 2.474"- 2.494".

The way length measurements get referenced in some of these discussions makes me think a lot of people don't have a good grasp on how long a .001 of an inch really is. The difference between 2.4775" and 2.484" is the thickness of the paper used to make a common envelope.

 

[Rflshootr]

I agree with thatguyshm. I'd trim them to 2.490 length then let the others catch up on the next firing or 2. But, keep an eye on the 2.490 length ones each reloading until you can trim them all the same.

 

[30BR]

Howdy,
It's newer savage .30-06
RCBS precision mic shows chamber to be SAAMI minimum
Sinclair chamber length tester shows brass can be 2.5" and be safe
Manual says max should be 2.494", trim to 2.484"

fire formed Winchester brass is all over the place. Mouths not square/tilted. Length, is 2.5 to Waaay less. Do I trim them all to be the same? Even if it's pretty short?
Not sure what do.
thanks in advance.

The brass may not be fully fire-formed yet. Even if its a minimum length chamber, it could be larger in diameter or have some other quirks. Trim only the ones that are longer than 2.490 to that, and shoot them all again before trimming to shortest one in the bunch.