Crimp dies

[eldermike]

I also learned something about crimping in general back when I was shooting bench rest rifle. Crimping is not necessary for anything other than getting a round into the chamber with the same OAL you started out with at the loading bench. There are tons and tons of writings on the net and in books concerning the usefulness or lack of with bullet crimping. Bench Rest shooters don't crimp.

So, with any method all you need is sufficient crimp to keep your assembly assembled until you pull the trigger. This is far less crimp than most people apply when reloading.

I use the Lee Factory crimp to remove the flare and then I test push the round on the bench, if it moves I need more but if it will not move I am done with crimp.

Everyone who writes pro or con on this issue brings up factory ammo at some point and they use this as a justification for excessive crimping of handloads. But the truth is; factory tolerances and stack up of same will not allow for custom light crimping. In order to insure sufficient crimping they use excessive on average, but they no choice.

There is another argument that crimping aids ignition and full burning of powder. Given that the chamber pressure is about 1/3-1/4 of peak before the bullet is engraved in rifling the added very few pounds pressure from a brass crimp seems insignificant in the overall pressure in the chamber.

Bottom line: Don't over crimp.

[CT_Shooter]

Good information, eldermike. There is an art to the science, which is most enjoyable.

Bottom line: Don't over crimp.

But, in a Henry's tube magazine, if you don't want your 2nd or 10th bullet moved deeper into its case, roll crimp just enough! Thanks for the good advice. Lifelong learning is a treasure for the human spirit.

[Jaker]

Taper crimp is for ammo like 9mm and 45 acp. Rimless cartridges.
For 44 mag and 45/70 you need a roll crimp to keep the bullets from moving in the brass under recoil while they are in the cylinder or magazine.
.

+1 ..... Each cal all have little different quirks . So no nothing should be put in stone which way is best in reloading ammo . I like to do all my crimps separate because I can feel the crimp and if there is a problem with brass you can pick it up there a lot of times . I try never to say the word reload .... I make custom ammo and it far better then factory ammo plus I can tailor the ammo for type of shooting I'm doing . My cowboy ammo is 750 fps . my defense ammo is 1000 fps and hunting at max fps .

Well said I like handload, also.

[ditto1958]

I didn't really know Crimp, but I'm sad to hear he has died. He will be missed.

Oh, wait- you mean dies that crimp ammo. Never mind.

[PJM]

If you shoot a plated handgun bullet like Berrys the manufacturer says use a mild taper crimp as a roll crimp may pierce the plate and could be shed and left in the barrel.

[clovishound]

I've used roll crimp dies with plated and never had that issue. I've switched to coated, and haven't looked back.