Anyone have good pictures of what a roll crimp looks like?

[ThumperACC]

I haven't reloaded any revolver rounds yet, so everything I reload is taper crimp. I would like to see what a roll crimp looks like and how it is different from a taper crimp. So if anyone has good pics I'd appreciate it.

Also, why do revolvers require a roll crimp?

Thanks,
ThumperACC

 

[LiveLife]

It's a sticky thread - http://www.thehighroad.org/showthread.php?t=469815

It's to keep bullets from pulling out of cases during heavy recoil in the cylinder. I suck at roll crimping, so those that are experts (like Walkalong) at roll crimping should be along to guide you.

 

[LiveLife]

Taper crimp pics - I tell you, those were some nice looking roll crimps!

 

[Sunray]

"...why do revolvers require a roll crimp..." They don't, depending on the cartridge and load used. Target loads don't need a crimp at all and are more accurate without one.
It's about pistol cartridges that headspace on the case mouth not using a roll crimp. Doing so will give you no headspace.

 

[gamestalker]

I learned my lesson a long time back regarding a good crimp being needed on revolver cartridges. The light loads aren't really an issue, it's the +P and other higher pressure loads that will walk a bullet out of the mouth, and among other things that can happen, it will lock your cylinder up nice and tight. Worse yet, if one or more cartridge's not in battery gets lit up because the powder charge becomes partially exposed, you can have a real bad day!

 

[Bmac1949]

good job on the crimping and pictures

 

[ThumperACC]

Thanks everybody.

BDS, thanks for the link to the sticky. I guess I missed it right there at the top of the page.

ThumperACC

 

[mdi]

For some powders, a heavy crimp is beneficial, H110/W296 especially. The "back pressure" is for a good consistant burn of the powder. I've seen pics of a wad of H110 stuck in a barrel (.44 Mag.) from incomplete ignition from light crimp and non-magnum primers. I shoot 5 different .44 magnums (99% lead bullets) and all loads get a roll crimp on the heavy side (WC820, 2400, Bluedot, and Unique powders).

I find a consistant/uniform crimp actually aids accuracy in my revolvers...