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View Full Version : Odd thing w/fire forming.



Harter66
01-02-2012, 08:26 PM
Not my 1st trip making little brass out of big brass or even 35 out of 22 or 45 from30.

This is about bottle neck ,comparitively,low pressure rifle cases sooting heavily. When I began having the issue w/45 Colts,38/357 Mags I annealed them and problem solved. I repeat that about every 10th load now . I formed some 7x57 from a selection of 06' that were orphans ,too heavy,mis-matched headstamps,5 of those,3 of these,the split necks. Anyway I torched the necks enough to blue line the 06' shoulder,and ran them through an 8x57 w/o the decapper. Rough cut to length, lubed and ran them through the 7x57 w/o the decapper. Violia' , cases for the 1908 Ovieda small ring Mauser. Since the lead pot was hot I did the neck dip and let them cool for a week or so . When I got to load them I ran them up to open the necks for the Sierra 120 spire points,no mould sorry, and loaded over 47.0gr of 4350. The Remmy and FC cases sealed up and matched the chamber dimentions,all of those cases matched and were slightly larger than those from the Lyman Dura Chrome dies. The WW Super X and Winchester cases not only had hard soot on the necks,shoulders,and half way down the case. Those cases showed little to no shape change the bolt lift was firm on closing but light on opening showing that the cases had formed.

No point beating myself up I'll just not use the Win cases and stick w/ the others.

Have others expirenced this?

runfiverun
01-02-2012, 10:17 PM
rem's fireform better for me in my ackleys too.
their brass is softer.
try upping the load a grain in the win's and try them again.

Harter66
01-03-2012, 12:38 AM
Thanks . Glad it wasn't just me. I guess I just never had all the factors line up just so before.

Chicken Thief
01-03-2012, 06:44 AM
When a case is shortend the wall thicknes gets larger.
So a shortend case needs higher pressure than a original case to do the same brass displacement.

Harter66
01-03-2012, 12:52 PM
Chicken,

I think the load was in the 30k psi range (2109.2 kilos per cm2).

I just thought it odd that 2 of the 3 major US brands would form up so well and the other behave as if work hardened . It is a small matter as I have somewhere in my stuff matched cases from another project from many years ago. If not this rifle is worth spending the money for new brass to sort and match into lots.