Always trimming dasher brass

[Patch700]

Since it no doubt is a sizing issue, I would like to know both the before and after sizing specifications of the fallowing:
- Web diameters below expansion line
- Web diameters above expansion line
- Shoulder diameters
- Lengths to shoulder datum
- OAL's
By accessing these measurements, should pin-point where the issue to be coming from.

Also, could color a case or two with a Sharpie, size it, and look to the wear for heavy contact area's.
Also make sure the die is thoroughly clean, and not a lube or brass build up.

My 2-Cents
Donovan

Hate to see these forums go unfinished so here's more info
Web dia on fired and sized brass is .471 . Just above that where the die quits sizing measures .470 fired and sized. Fired shoulder measures .4595. Sized shoulder measures .455. Don't know how to measure length to shoulder datum but I'd call it 1.195 on both. Oal 1.550. Hope this helps. With the spring back in the brass I'd say my dies are sizing about 6k at the shoulder

There is where you are seeing the growth... With the case being sized 6thou at the shoulder case junction there is a lot of brass to move , and it can only go one place and thats up.

 

[K redden]

If you don't know how to measure length to datum on shoulder how did you set dies up? This is what that tool included with your die set is for. Measures how far you are bumping your shoulders back

And according to your above post your OAL is 1.550? So I thought you were having problems with brass growing too much. What is length before sizing and after?
[/
. As far as length to datum with the datum collar on my calipers a fired brass is 2.227 and sized is 2.2255 . The brass is 1.550 cause that's where I have my trimmer set to. Then I load and fire it and and it is 1.550. Then I full size it and it grows about 2k

 

[boltfluter]

I had the exact same situation with my 6.5 x47 dies. I had them make a custom die for my chamber and got full credit for the returned die. New die sizes the shoulder body junction .001 instead of .006. I would speak to John personally and he will make it right. Good luck.

Regards, Paul

www.boltfluting.com