Roll crimp & Fold crimp

[dsh1106]

Hey out there I need some help.

I've spent the last day or so going through this section page by page, and didn't see what I was looking for.


I understand you can't just willy nilly swap components while reloading shot shells, but what about the crimp??

Can I substitute a roll crimp for a fold crimp ???


Thanks
Scott

[Hogtamer]

https://ballisticproducts.wordpress.com/2012/12/14/does-a-shotshell-roll-crimp-raise-or-lower-pressures-versus-a-fold-crimp/

[vzerone]

Good person to ask this too is runfiverun.

[labradigger1]

I can think of no load that would be better with a fold crimp. Roll crimp is much slower to do but it also allows for more uniform ballistics and a better waterproof seal. Usually less pressure also.

[vzerone]

I remember my neighbor talking to runfiverun on another forum and he said the fold crimp gave the higher of pressure between the two types of crimps. I can tell you, though, that the BPI roll crimping tool you put in your drill press is faster then you can load the shells under the drill/tool. When you set the depth stop it makes perfect roll crimps. I'm talking plastic hulls of course.

[RMc]

Roll crimped 2.75" shells have essentially the same internal loaded volume as 3" folded crimp shells of the same brand/type/basewad height. Likewise a roll crimped 2.5" shell would have essentially the same internal loaded volume as a 2.75" fold crimped shell of the same brand/type/basewad height.

A true comparison between Fold and Roll crimp pressure difference would require loaded shotshells with the same internal loaded volume.

[Duckiller]

Not sure how you get a rolled crimp on plastic hulls. Folded crimps that started out that way are easy to do. I have never seen factory plastic hulls with roll crimps. All my duck loads have folded crimps and are sealed to keep out water. I am old enough to have hunted with paper hulls that had rolled crimp. When wet they would swell and jam in automatic shot guns. Folded crimp also eliminated the over shot wad thar never did a pattern any favors. Platic wads and plastic hulls came in about the same time. I believe there is a reason besides money that American made shells have folded crimps. I think they shoot better.