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RHarris · December 14, 2001, 03:17 AM

I've reloaded a lot of revolver rounds but am just now starting to reload semiauto rounds. I've done a search concerning crimping them and haven't really figured it out yet.

I think I understand the differences between the roll crimp and taper crimp.

I purchased some new Hornady Titatanium Nitride dies to load 45ACP. Previously I have worked with Lee Dies for revolvers. The instructions with the Hornady dies say nothing about taper crimping or roll crimping, just "crimping". Can someone tell me what kind of crimping they perform? I've read other posts about roll crimping vs taper crimping and have been lead to even more confusion. If autoloaders are not meant to be roll crimped, then why would die sets for autoloaders have the roll crimp function?
If die sets for autoloaders do not normally taper crimp and a taper crimp is really necessary, why don't the manufacturers include a taper crimp die with the set?

The cast lead bullets I have do not have a crimp groove. Loading for revolvers, I could see the effects of a roll crimp very well. I've experimented with these new dies and no matter how much I adjust the die, there is no "roll" noticed. There is still a nice sharp edge left at the case mouth. Is this because there is no crimp groove for the brass to "roll" into or because the die doesn't roll crimp?

Other posts I've read have a lot of differing opinion concering crimps and whether or not they are necessary. Some have said the taper crimp simply smooths out the bell in the case created by the expander die.

Here is what I've done so far. I followed the instructions provided with the Hornady dies to make powderless, primerless dummy rounds to see what I'd get. I got the right seating depth set up and adjusted the crimp (whatever kind it is) just a little to where the bell in the case is gone. I then took a barrel and put the rounds in the chamber to see how they would fit while comparing them to new factory loaded ammunition and it's fit and heatspacing. I've ended up with something that appears it will feed and extract smoothly. I cannot push the bullets deeper into the cases with fingers; the bullets appear to be very tightly held in the case neck (can actually see an outline in the brass where the bullet is seated to). I'm failing to see how a crimp in this cartidges is even necessary, other than to get rid of the flare from expanding.

Any help would be appreciated. I'd like to make sure I'm not doing anything unsafe before putting powder in one of these and making it go bang.

December 14, 2001, 03:17 AM	#1
RHarris Senior Member Join Date: June 18, 2000 Posts: 416	Confused about taper crimping I've reloaded a lot of revolver rounds but am just now starting to reload semiauto rounds. I've done a search concerning crimping them and haven't really figured it out yet. I think I understand the differences between the roll crimp and taper crimp. I purchased some new Hornady Titatanium Nitride dies to load 45ACP. Previously I have worked with Lee Dies for revolvers. The instructions with the Hornady dies say nothing about taper crimping or roll crimping, just "crimping". Can someone tell me what kind of crimping they perform? I've read other posts about roll crimping vs taper crimping and have been lead to even more confusion. If autoloaders are not meant to be roll crimped, then why would die sets for autoloaders have the roll crimp function? If die sets for autoloaders do not normally taper crimp and a taper crimp is really necessary, why don't the manufacturers include a taper crimp die with the set? The cast lead bullets I have do not have a crimp groove. Loading for revolvers, I could see the effects of a roll crimp very well. I've experimented with these new dies and no matter how much I adjust the die, there is no "roll" noticed. There is still a nice sharp edge left at the case mouth. Is this because there is no crimp groove for the brass to "roll" into or because the die doesn't roll crimp? Other posts I've read have a lot of differing opinion concering crimps and whether or not they are necessary. Some have said the taper crimp simply smooths out the bell in the case created by the expander die. Here is what I've done so far. I followed the instructions provided with the Hornady dies to make powderless, primerless dummy rounds to see what I'd get. I got the right seating depth set up and adjusted the crimp (whatever kind it is) just a little to where the bell in the case is gone. I then took a barrel and put the rounds in the chamber to see how they would fit while comparing them to new factory loaded ammunition and it's fit and heatspacing. I've ended up with something that appears it will feed and extract smoothly. I cannot push the bullets deeper into the cases with fingers; the bullets appear to be very tightly held in the case neck (can actually see an outline in the brass where the bullet is seated to). I'm failing to see how a crimp in this cartidges is even necessary, other than to get rid of the flare from expanding. Any help would be appreciated. I'd like to make sure I'm not doing anything unsafe before putting powder in one of these and making it go bang.