[F. Guffey]

I use a case/forming die from RCBS. I form the case first, trim .254 from the top of the forming die with a hack saw, finish with a file then lower the ram, then I full length size the case to 8mm57, again I do not pass up the opportunity to adjust the case to the chamber, when using 30/06 cases to form 8mm57 the reloader can not miss, the shoulder on the 30/06 is ahead of the shoulder on the 8mm57 .121 thousands. Before forming dies and before Berdan primed cases were available, the 8mm57 die was used, shoulders developed dents, folds and wrinkles, the dents popp out when fired, the folds became creases and stayed that way. The trim/form die increases the success over the 8mm sizer die.

Bumping sounds like an accident, when adjusting the (A) die to size I control the gap between the die and shell holder with a feeler gage, rather than 'bump' the shoulder back I adjust the gap to avoid moving the shoulder further back than necessary.

On my press(es) and dies full length sizing is full length sizing, the die is adjusted down to the shell holder with an addition guesstimate of a turn 1/8 to 1/4, that is an additional .0085 to .017 thousands, cases sized in this manner are sized to .000 or .005 shorter than a go-gage length chamber from the head of the case to it's shoulder, if my shell holder does not have a deck height of .125 and the die does not size to minimum length I can send them back and have it replaced with a die that is as advertised, the dies are labeled Precision, Competition, bench rest, New Dimension, sizing is not an accident, I expect predictable results, and I do not have to purchase a tool box of tools to verify the results.

So rather than size cases mindlessly by screwing the die down to crush settings, I control the crush or shoulder set back which is anything but 'bump' I would call it 'wreck' as in change, establishing the shoulder .121 further back than the shoulder of the parent case allows the relaoder to establish case length from the case head to the shoulder to effect head space, for the most part I have form/trim dies from 243 to 300 Win Mag.

Success rate, new unfired cases, perfect. Once fired, 2ND best. When necking up as in 30/06 to 3387 or 35 Wileen do not use nickel cases, 30% of the necks could split on once fired cases. When annealing, anneal the case down to the point the new shoulder will be established.

When necking up 30/06 to 35 Whelen I have split 5 out of 100 cases, when using 280 Remington new cases the results is about the same, again the difficult part is trying to find cases with the case length from the head of the case to the shoulder longer than necessary and finding cases that do not shorten when necked up, 30/06 cases can be customed fit to the chamber of the 8mm57, 7.7 Japanease, 308 Winchester etc..

I use a RCBS forming/trim die, cases must be full length sized after forming, I have neck sizer dies and samll base dies, I choose not to use them, I use the full length sizer to neck size, partial neck size, neck size with partial body sizing and full length sizing but I know the size of the case I want.

F. Guffey