A roll crimp vs. taper crimp question.

[Polish-Jack]

I know that taper crimps are used with cartridges that space at the mouth and roll crimps can cause problems with such cartridges, but what is the physical difference between a roll crimp and a taper crimp?

 

[Canuck223]

As it suggests, the taper crimp is just a beveling of the case into the bullet. The Roll crimp literally rolls the edge of the case into the bullet. If you've seen a flanged end of a pipe, imagine the opposite.

 

[CdnCombatMedic]

what crimp should you use for 223 for an AR?

 

[Canuck223]

what crimp should you use for 223 for an AR?

Any crimp die sold for the .223 Rem will be a taper crimp.