[You bring up a point to ponder here , with that line of thinking , how can the same die be used for the 45 S&W , 45 Auto Rim as well as the 45ACP ( 90864 ) the S&W is a longer case , thus moving the crimp to a different location on the case ?
The same would apply to the 45LC , 454 Casull and the 45 Webley Mk2 ( 90865 ) as well as the 32 S&W and 32 H&R mag ( 90067 )
stimpy
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The Lee factory crimp die for these straight wall calibers works different than the one for bottle neck rounds. For the straight wall cases you can screw the die up and down like a regular roll or taper crimp die. Basically it is a taper crimp die that is tighter at the rear so it will size the base of the case as well. The Lee factory crimp die for bottle neck cases works like this. It has a collet inside the die body that the bottom of the collet must come into contact with the shell holder as the ram is raised and it pushes the collet up into the die body which causes fingers to squeeze inward around the case neck with equal pressure all the way around the case mouth and it will make it's own crimp groove in the bullet also. This is why case length and neck length is so important.