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Which crimp to use

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06 February 2002, 07:16
R-WEST
Which crimp to use
So far, I've seen: Taper Crimp, Roll Crimp, Factory Crimp, and Profile (?) Crimp dies offered for handgun cartridges.

Not having been into handgun reloading that much previously, I used whatever crimp die came with the set, or just screwed down the seater die to crimp. My handgun shooting has recently ramped up sharply (nephew recently became a PA State Trooper, and we're shooting a lot. By the way, you can now drive as fast as you want in PA - just mention that you know R-WEST ). Seeing all these different crimp dies now has me wondering. Which one is used when?

Thanx,

R-WEST

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"it is up to God to judge these terrorists; it is up to us to arrange their meeting" Gen. Norman Schwarzkopf

06 February 2002, 07:56
<jd_1>
On semi-auto pistols use a taper crimp. On revolvers use a roll or a "factory" crimp.
06 February 2002, 08:43
<txhunter>
R-West
Typicaly you want to use a crimp that holds the bullet in place.hehehe
06 February 2002, 09:25
<fa18hooker>
I haven't noticed a difference in crimping or not crimping with handgun rounds...there's no real need to, and it weakens the brass.
06 February 2002, 10:17
Mule Skinner
If you are loading for a semi-auto then a light taper crimp is called for. You don't want to crimp too much because most semi-auto's (9mm, .40 S&W) headspace on the cartridge mouth. For revolver cartridges like the .357 or .44 Magnum I use a heavy profile crimp. It has increased the velocity, made the standard deviation smaller, and increased the accuracy of my loads when compared to a standard roll crimp.

Oh, and if you come to Texas, just mention my name and they will give you a speeding ticket! :-)

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"it is up to God to judge these terrorists; it is up to us to arrange their meeting" Gen. Norman Schwarzkopf

[This message has been edited by Shark Bait (edited 02-06-2002).]

06 February 2002, 11:27
R-WEST
Shark Bait - Hey, what's the big idea using my signature? Now I have to go find another one

txhunter - I think that only applies to MatchKings intended for use on armadillos, 'coons and/or chipmunks.

fa18hooker - A lot of the heavier handgun loads in 357/44/45 Colt using H110 and/or W296 recommend use of a heavy crimp. Have you had any experience with those powders? You're right about it working the brass to death, so, if I don't have to do it, I won't.

I was reading somewhere, I think in Handloader, of a test using the same handgun loads with no crimp, medium crimp and heavy crimp, and the heavy crimped loads had higher velocities and better accuracy. I'll see if I can find it.

R-WEST

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"it is up to God to judge these terrorists; it is up to us to arrange their meeting" Gen. Norman Schwarzkopf

06 February 2002, 14:49
<Martindog>
Taper crimp for auto rounds.

I thought Redding's Profile crimp was just another Roll crimp.

Lee's FCD for handguns post-sizes and crimps the round in one operation. The crimp is applied effectively across the entire length of the seated portion of the bullet rather than just the case mouth area (taper/roll crimps). I have no experience with their handgun FCD but their main claim to fame seems to be along the lines of functional reliability rather than accuracy. I guess it depends on your application.

Bottomline though is heavy recoiling revolver rounds have been effectively crimped for years using roll crimps with complete reliability. I can't think of too many auto rounds that require a good tight crimp though due to recoil. The area you need to pay close attention to here is whether or not the neck tension is high enough to prevent deeper seating as they slam into feed ramps and such. Just make sure neck tension is good and squeeze case mouths flush with bullet to provide a nice shelf to headspace on.

Martindog

06 February 2002, 18:18
DanD
I have not ever had much problem not crimping 45 for use in my 1911, basically I believe that the single stack mag is tight enough that it doesn't leave much room for the bullets to creap out. On the other hand I tried not crimping 357Mag for use in a Vaquero and found that the slick little cowboy leads creaped quite a bit to at one point where the cylinder actually got jammed.
But basically I think you should go with what works in the gun, if you can get away without crimping, good, if not you'll just have to buy new brass more often.
06 February 2002, 19:31
<auto>
Not much to add, except if the weapon you are shooting is an "auto", you will need to taper crimp. And most of my experience is with the .45 ACP. The mouth of the .45 ACP must be a certain diameter to chamber properly in the barrel. This is because the cartridge head spaces on the mouth. I am not certain, but I suspect that the 9mm, and the 40 S&W are the same. If you get feeding problems, this is where to look.