When forming/sizing cases for short chambers
Not true, the shim between the deck of the shell holder and case head can increase the presses ability to overcome the cases resistance to sizing.
The reloader and smith use fixed gages like the go-gage, no go-gage and the field reject length gage; they are also locked into bumping the shoulder back. They all go for the .002" bump...and then they just quit.
The shell holder and die are designed to return the case to minimum length; minimum length is the same as full length sized. Again, I have always thought grinding the shell holder and or die is a bad habit. Anything that can be accomplished by grinding I can accomplish with a feeler gage.
When shortening the case from the shoulder/datum to the case head I can shorten the length of the case from the shoulder to the case head .011" with a RCBS shell holder and a feeler gage. If I find a rifle with a short chamber I determine how short in thousands with formed cases. There is another way but at this rate we will never get around to discussing the method and or technique.
Same with competition shell holders; the maximum length that can be gained with the competition shell holder is .010", with a feeler gage I go straight to .016" for my long 30/06 chamber. I use a feeler gage to adjust the die off the top of the shell holder. Again, When I want that .002" clearance I adjust the die off the shell holder .014".
When forming and sizing cases for critical fits I use new and or once fired cases.
F. Guffey
.I just saw UN last post so I'll post a pic on the feeler gauge idea as well . This lifts the case up and allows you to size the case even shorter then a standard shell holder will allow . That would make for a mighty short chamber though
Not true, the shim between the deck of the shell holder and case head can increase the presses ability to overcome the cases resistance to sizing.
The reloader and smith use fixed gages like the go-gage, no go-gage and the field reject length gage; they are also locked into bumping the shoulder back. They all go for the .002" bump...and then they just quit.
The shell holder and die are designed to return the case to minimum length; minimum length is the same as full length sized. Again, I have always thought grinding the shell holder and or die is a bad habit. Anything that can be accomplished by grinding I can accomplish with a feeler gage.
When shortening the case from the shoulder/datum to the case head I can shorten the length of the case from the shoulder to the case head .011" with a RCBS shell holder and a feeler gage. If I find a rifle with a short chamber I determine how short in thousands with formed cases. There is another way but at this rate we will never get around to discussing the method and or technique.
Same with competition shell holders; the maximum length that can be gained with the competition shell holder is .010", with a feeler gage I go straight to .016" for my long 30/06 chamber. I use a feeler gage to adjust the die off the top of the shell holder. Again, When I want that .002" clearance I adjust the die off the shell holder .014".
When forming and sizing cases for critical fits I use new and or once fired cases.
F. Guffey