30 BR length

Have fireformed brass, need overall length to trim to.
Robinette reamer.
Getting alot of answers, guess I need more.

Steve
 
Is your chamber a no-turn chamber?? If not what did you stop the neck turner against?? Were the cases all the same length out of the box??

Mike Swartz
 
Case Length

I have the Robinett Reamer, and we trim to 1.510.

The way that most make thier 30BR cases, (by using a press and mandrel to neck them up to 30), the cases will come out quite a bit shorter than the 1.560 of the originol 6BR case.


If I had it to do again, I would have gotten my reamer ground a little longer. We make our cases by blowing them out to 30 caliber in a 6mm barrel in a 6BR chamber with the neck reamed out to .330. This produces a case that is about 1.550 in length after fireforming........jackie
 
thanks

Mike and Jackie,

Thanks for the reply, most after 3 firings were around
1.140 - 1.150. Fireformed with bullet / 33-4198.

Thanks
 
Steve,
I would be weary of using the rounds that are on the 1.410 end. That is a lot of space from the end of the round to the end of the chamber not to mention a great difference between the individual rounds.
I would group the cases that are closest to 1.510 and toss the rest.
If you can, segregate those that are EXACTLY the same length and then see what shoots/loads the easiest in your chamber. No sense in adding a variable like case length if you can avoid it.
Were they all the same length prior to fireforming?
Just my 2cents,
Mike
 
Last edited:
Thanks for the reply, most after 3 firings were around 1.140 - 1.150.

Steve...are you sure on that measurement? 1.140-1.150? :confused: Something funny here goes on, as we say in South Dakota. :D

A new Lapua 6BR case starts out around 1.550-1.555 and shortens to around 1.535 when expanded to .30 over a mandrel. The 'Robinett' spec. chamber is 1.520 long. I trim to 1.510 and they shorten to 1.505-ish after fireforming. I let 'em be until they reach 1.510 and then trim as needed to keep 'em there. Lots of people simply trim to 1.500 and trim again at 1.510 when needed.

Maybe double check your figures, okay? -Al
 
Oops

[
Al,
You are right It should of been 1.540-1.550

Zane,

First match with gun was good. Was in first place
till the last target. Lost by 1 x, Came in 2nd. Not
bad for only shooting gun 3 times. By the way
all matches with coated bullets, never cleaned
once. Kinda scary, never done that before.

Steve Huff

QUOTE=Al Nyhus;455308]Steve...are you sure on that measurement? 1.140-1.150? :confused: Something funny here goes on, as we say in South Dakota. :D

A new Lapua 6BR case starts out around 1.550-1.555 and shortens to around 1.535 when expanded to .30 over a mandrel. The 'Robinett' spec. chamber is 1.520 long. I trim to 1.510 and they shorten to 1.505-ish after fireforming. I let 'em be until they reach 1.510 and then trim as needed to keep 'em there. Lots of people simply trim to 1.500 and trim again at 1.510 when needed.

Maybe double check your figures, okay? -Al[/QUOTE]
 
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