.45 ACP Lee Factory Crimp Die Question

Pitbull · January 1st, 2009, 08:39 PM

Hey everyone -

How much crimp is too much? Is it possible to over/under crimp?

Usually, the instructions that come with the lee products are pretty good but the instructions with the factory crimp dies are lacking.

What should I be looking for?

Ghuqu2 · January 1st, 2009, 10:38 PM

Light crimp on 45 acp except w/ cannular ~1/8-1/4 turn of die if you follow the setup instructions. More crimp on bullets w/ cannular. Also when in doubt call them, 262-673-3075. The have answered many of my questions and are happy to hear from their customers.

cvhoss · January 2nd, 2009, 02:53 AM

Quote:

Originally Posted by Pitbull

............Is it possible to over/under crimp? ...............

Yes.

If you under crimp, recoil will have an effect on the remaining cartridges in the magazine, usually driving the bullets further into the case, plus the bullets will be driven into the case further as the cartridges hit the feed ramp during chambering. Also, too little crimp can result in not all of the case mouth flare being removed and result in difficult, if not impossible, chambering.

If you over crimp on a rimless case like the 45 ACP, you create problems because the cartridge headspaces on the case mouth. By excess crimping you reduce the case mouth diameter too much and the cartridge can fall too far into the chamber.

The thing I suggest is to get the dimensions from a cartridge drawing and progressively increase your crimp, measuring with calipers at each increase, until you reach the recommended dimensions. Below is a drawing of a 45 ACP showing that the case mouth dimensions should be 0.4730".

Hoss

msgt/ret · January 2nd, 2009, 03:03 AM

When it comes to semi-auto rounds that headspace on the case mouth I have found it better to use a taper crimp die. While this does require another step in reloading it does not change the over all length of the case, which may occur with roll crimping.

cvhoss · January 2nd, 2009, 03:53 AM

Quote:

Originally Posted by msgt/ret

When it comes to semi-auto rounds that headspace on the case mouth I have found it better to use a taper crimp die. While this does require another step in reloading it does not change the over all length of the case, which may occur with roll crimping.

Just to clarify, the Lee Factory Crimp Dies for auto cartridges are a taper crimp die.

Lee Carbide Factory Crimp Die

A carbide sizer sizes the cartridge while it is being crimped so every round will positvely chamber freely with factory like dependability. The adjustig screw quickly and easily sets the desired amount of crimp. It is impossible to buckle the case as with a conventional bullet seating die. Trim length is not critical so this extra operation takes less time than it would if cases were trimmed and chamfered. Revolver dies roll crimp with no limit as to the amount. A perfect taper crimp is applied to auto-loader rounds. The crimper cannot be misadjusted to make a case mouth too small to properly head-space.

Hoss

Darth AkSarBen · January 6th, 2009, 12:33 AM

I called them about this, and if they are newer Lee 3 die set (mine are Lee Carbide) then the newer bullet seating in .45 are also taper crimp dies and you do not need to buy an additional taper crimp die. If, however, you have another brand of die, say RCBS for an example, and wish to put in a factory taper crimp, then you can buy the LEE taper crimp die and do the job in an extra step.

kazzaerexys · January 6th, 2009, 11:15 AM

Quote:

Originally Posted by Darth AkSarBen

If, however, you have another brand of die [...] then you can buy the LEE taper crimp die and do the job in an extra step.

I just bought a Lee factory crimp for my Dillon 550B, for which I have the standrad Dillon dies in .45 ACP. Isn't the Lee just a drop-in replacement for the Dillon crimp die in station four?

cvhoss · January 6th, 2009, 11:19 AM

Quote:

Originally Posted by kazzaerexys

I just bought a Lee factory crimp for my Dillon 550B, for which I have the standrad Dillon dies in .45 ACP. Isn't the Lee just a drop-in replacement for the Dillon crimp die in station four?

Yes.

Hoss

sgtD · January 6th, 2009, 11:23 AM

Quote:

Originally Posted by Darth AkSarBen

I called them about this, and if they are newer Lee 3 die set (mine are Lee Carbide) then the newer bullet seating in .45 are also taper crimp dies and you do not need to buy an additional taper crimp die. If, however, you have another brand of die, say RCBS for an example, and wish to put in a factory taper crimp, then you can buy the LEE taper crimp die and do the job in an extra step.

That's good to know. Now I have to make sure I get the right one when I buy one. I plan to get one very soon. Thanks.

Darth AkSarBen · January 6th, 2009, 09:22 PM

This is the site at Cabela's Where I got my carbide 3 die set. From the lady at Lee Precision, the factory taper crimp is not needed as this set has it built into the seating die. Works for me pretty well.
Hoo Ra

January 1st, 2009, 08:39 PM	#1
Pitbull Member Join Date: Jan 2008 Location: Alexandria, VA Posts: 51	.45 ACP Lee Factory Crimp Die Question Hey everyone - How much crimp is too much? Is it possible to over/under crimp? Usually, the instructions that come with the lee products are pretty good but the instructions with the factory crimp dies are lacking. What should I be looking for?

January 1st, 2009, 10:38 PM	#2
Ghuqu2 Member Join Date: Apr 2007 Location: Missouri Posts: 289	Light crimp on 45 acp except w/ cannular ~1/8-1/4 turn of die if you follow the setup instructions. More crimp on bullets w/ cannular. Also when in doubt call them, 262-673-3075. The have answered many of my questions and are happy to hear from their customers. __________________ "The millions of people, armed in the holy cause of liberty, and in such a country as that which we possess, are invincible by any force which our enemy can send against us." Patrick Henry 1775 Vegetarian: Indian for inept hunter.

January 2nd, 2009, 03:03 AM	#4
msgt/ret Senior Member Join Date: Jun 2006 Location: North Carolina Posts: 1,018	When it comes to semi-auto rounds that headspace on the case mouth I have found it better to use a taper crimp die. While this does require another step in reloading it does not change the over all length of the case, which may occur with roll crimping. __________________ When you have to shoot, shoot. Don't talk. "Don't forget, incoming fire has the right of way."

January 6th, 2009, 12:33 AM	#6
Darth AkSarBen Member Join Date: Jul 2008 Location: Near Fennville, MI USA Posts: 115	I called them about this, and if they are newer Lee 3 die set (mine are Lee Carbide) then the newer bullet seating in .45 are also taper crimp dies and you do not need to buy an additional taper crimp die. If, however, you have another brand of die, say RCBS for an example, and wish to put in a factory taper crimp, then you can buy the LEE taper crimp die and do the job in an extra step. __________________ Vern http://Taurus45ACP.com My wesbsite with many pro-gun links. Carry Taurus 24/7 Pro in .45 ACP Last edited by Darth AkSarBen; January 6th, 2009 at 12:41 AM.. Reason: correction

January 6th, 2009, 09:22 PM	#10
Darth AkSarBen Member Join Date: Jul 2008 Location: Near Fennville, MI USA Posts: 115	This is the site at Cabela's Where I got my carbide 3 die set. From the lady at Lee Precision, the factory taper crimp is not needed as this set has it built into the seating die. Works for me pretty well. Hoo Ra __________________ Vern http://Taurus45ACP.com My wesbsite with many pro-gun links. Carry Taurus 24/7 Pro in .45 ACP Last edited by Darth AkSarBen; January 6th, 2009 at 09:24 PM.. Reason: correction

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