Crimp or Not to Crimp

northwingnut · March 4, 2012, 06:58 AM

I am very new to reloading and I started with my 10mm. I read a couple different manuals and they are all pretty vague about the type of crimp needed.

On 10mm they say you can taper crimp if desired. I also want to reload .40 cal and the manual says no crimp is needed. Is that true or should I use a seperate factory crimp die for both?

steve4102 · March 4, 2012, 08:10 AM

The crimp is a must if you want you loads to feed and function in a semi-auto. The crimp in these two rounds is called a "taper" crimp. You apply only enough crimp to remove the flare plus maybe a thou more. I crimp both my 40 and 10mm to .421.

northwingnut · March 4, 2012, 08:42 AM

So can I use the seating and crimping die to do both in one action or does that aply a roll crimp?

IllinoisCoyoteHunter · March 4, 2012, 08:48 AM

Yes, use your seating die to both seat the bullet and taper crimp. The taper crimp, as stated, just pushes the flare back against the bullet.

I decided to explain how to set up your third die so you can save money and not buy a dedicated crimp die.

This is how I do it, if you care:

1. Put a case that has been sized and flared into the shell holder. Lower the handle on your press, which will raise the case to the top of the stroke. Then, screw the seating/crimp die into the press until you feel the crimping portion of the die contact the case mouth. Once this happens, back the die out one full turn. Tighten lock ring.

2. Make sure your bullet seating stem is backed almost all the way out. Put a bullet in the case and run it up into the die. At the top of the stroke, run your seating stem down untill you feel it contact the tip of the bullet. Lower ram and continue to screw in seating stem until you have seated the bullet to your desired COL (cartridge overall length).

3. Now, back your seating stem almost all the way out. Run the round back into the die. Loosen your die lock ring and screw the die body down untill you feel it come in contact with the case mouth (again...you did this in step #1). Once it comes in contact, you know that as you screw the die body down further, you will be applying more crimp. Keep screwing the die body down until you have achieved your desired amount of crimp. Once achieved, tighten die lock ring.

4. Run the round back up into the die and at the top of the stroke, screw in your seating stem until it comes in firm contact with the bullet. Now you can seat and crimp with the same die with no problems. Remember, the taper crimp just removes the flare. It should not dig into the side of the bullet.

Hope this helps.

steve4102 · March 4, 2012, 08:48 AM

All of my seating dies apply a "taper" crimp, can't speak for your's, what brand are they?
I crimp and seat in different steps with a dedicated crimp die.

primerman · March 4, 2012, 10:42 AM

To get a consistent crimp your cases should all be close to the same length.

TXGunNut · March 4, 2012, 11:15 AM

ICH's method generally works for roll crimp dies as well, simpler than it sounds. I generally check the OAL after the final adjustment as well. I only use a dedicated TC die when the crimp profile on my seating die doesn't give me the results I'm looking for. I use range brass for .45 acp and the case length varies a bit. My seat/crimp die has a bit more drastic taper and a case a few thousandths too long will receive too much crimp, one too short will get very little crimp. My dedicated TC die has a more gradual taper and all reasonable case lengths get an adequate crimp.

NESHOOTER · March 4, 2012, 11:44 AM

[QUOTE][Yes, use your seating die to both seat the bullet and taper crimp. The taper crimp, as stated, just pushes the flare back against the bullet.

I decided to explain how to set up your third die so you can save money and not buy a dedicated crimp die.

This is how I do it, if you care:

1. Put a case that has been sized and flared into the shell holder. Lower the handle on your press, which will raise the case to the top of the stroke. Then, screw the seating/crimp die into the press until you feel the crimping portion of the die contact the case mouth. Once this happens, back the die out one full turn. Tighten lock ring.

2. Make sure your bullet seating stem is backed almost all the way out. Put a bullet in the case and run it up into the die. At the top of the stroke, run your seating stem down untill you feel it contact the tip of the bullet. Lower ram and continue to screw in seating stem until you have seated the bullet to your desired COL (cartridge overall length).

3. Now, back your seating stem almost all the way out. Run the round back into the die. Loosen your die lock ring and screw the die body down untill you feel it come in contact with the case mouth (again...you did this in step #1). Once it comes in contact, you know that as you screw the die body down further, you will be applying more crimp. Keep screwing the die body down until you have achieved your desired amount of crimp. Once achieved, tighten die lock ring.

4. Run the round back up into the die and at the top of the stroke, screw in your seating stem until it comes in firm contact with the bullet. Now you can seat and crimp with the same die with no problems. Remember, the taper crimp just removes the flare. It should not dig into the side of the bullet.

Hope this helps./QUOTE]

I think you did very well explaining this die setup and the Lymans reloading handbook #49 states one can put a modest crimp as the .40,9mm, and little to no crimp on the .45.
I use the Lee FCD and I do as ICH states then I can make the final ajustments to the crimp as I need/want.

thedaddycat · March 4, 2012, 07:35 PM

ICH, very nice description on the adjustment procedure. That one's a keeper. Do you use the same procedure when doing bottleneck rifle cases that will be crimped?

I have some sets of dies where I got the Lee Pacesetter dies (which come with the crimping seating die and a FCD) and then the Collet sizing die set to go with it. The Collet die set comes with what Lee calls a "Dead Length" seating die. This seating die will not crimp the case. Other chamberings I got the Deluxe Rifle die sets for. It comes with the FL and Collet sizing dies and a crimping seating die (not the DL seating die), but no FCD. I got a FCD for those chamberings. For some of my handloading I plan on just neck sizing fire formed brass for bolt action rifles, which do not require a crimp.

IllinoisCoyoteHunter · March 4, 2012, 08:12 PM

I only SLIGHTLY "crimp" my .223 CAST boolits loads. The only reason I do this is because I have to slightly flare the brass mouth to avoid shaving lead when seating the boolit. I use a Lee FCD to just push the case mouth back flush against the boolit. Nothing more, nothing less.

For all other jacketed rifle loads, I never crimp, whether running them through a semi or bolt rifle.

northwingnut · March 4, 2012, 08:59 PM

Thank you very much ICH. That is pretty simple and makes sense.

Hammerhead · March 4, 2012, 11:49 PM

I use a separate Redding taper crimp die in 10mm and .40 to remove any trace of flare, no crimp is applied.

northwingnut · March 5, 2012, 01:05 AM

What is the point of using two dies? I have heard people say that it is somehow more accurate but I don't see why.

NWPilgrim · March 5, 2012, 02:22 AM

Using a separate crimp die is especially useful when you are loading a lot of lead bullets. If I use a combination seat/crimp die it eventually gets clogged with lube and lead shaving and changes the seating depth gradually. I could periodically scrub out the seating die, or just use a separate crimp die.

However, If I only seat in that die it does not scrape off as much lead and lube as when trying to crimp at the same time. I shoot mostly lead bullets in handguns calibers so all my handgun turrets are set up with four dies: sizing, expander/powder through, seat (with crimp disabled), and taper crimp (or roll crimp for revolvers).

For rifle, most seating dies do not have built in crimping, so if you want to crimp for semi-auto use then you likely need a separate crimp die for it.

Remember, whether you use taper crimp or FCD you only need to kiss the case mouth with it to remove the bell, unless you are roll crimping into a cannelure on revolver or rifle.

Scimmia · March 5, 2012, 02:33 AM

Quote:

What is the point of using two dies? I have heard people say that it is somehow more accurate but I don't see why.

Yeah, I don't buy it when talking about cartridges like 10mm or 40 S&W. If you're getting lead and lube shavings like NWPilgrim talks about, you're either not belling enough or crimping too much. Bottleneck rounds or revolver rounds are different, I can see crimping with a separate die there, but not semi-auto rounds that headspace off the mouth.

NWPilgrim · March 5, 2012, 03:42 AM

That may be your experience. Good for you. That is not a universal truth however. If you use one die and works well for you then great! Don't change anything.

For myself, the lead bullets I can find at a good price have flecks of lube all over them. So just sliding into the case is going to scrape off some fleck of lube and after a few hundred rounds that adds up, even on the pistol cases. I have some other lead bullets that are very clean and do not do that but they cost 25% more than the other.

There is no ONE way to reload. Everyone uses different component combinations and techniques for different purposes. There is absolutely nothing wrong with using a fourth die and at a one time cost of $10 per cartridge I find it worth being able to shoot 25% cheaper lead bullets for the next 30 years (God willing). I have recouped my cost many times over. And the extra time to pull through another die is made up for not having to remove, disassemble, clean, reassemble, install the seating dies every couple of hundred rounds.

IllinoisCoyoteHunter · March 5, 2012, 09:19 AM

Quote:

If you're getting lead and lube shavings like NWPilgrim talks about, you're either not belling enough or crimping too much.

I have also found this to be true. Never found a need for a seperate crimp die when loading for pistol and most rifle rounds, with the only exception being cast .223 loads, as I stated above. To each their own. Whatever works for you.

Hammerhead · March 5, 2012, 11:36 AM

I use a separate crimp die because I use a competition seater die that has no crimp ring in it.

Bullet shaving is prevented by the case mouth flare and good bullet alignment.

I do use a single seater/crimp die in .44 special and .45 Colt and don't get any shaving even with a solid roll crimp.

It is possible to shave a lead or plated auto bullet if you have the crimp set too heavy because they have no crimp groove.

March 4, 2012, 11:15 AM	#7
TXGunNut Senior Member Join Date: January 16, 2010 Location: If you have to ask... Posts: 2,860	ICH's method generally works for roll crimp dies as well, simpler than it sounds. I generally check the OAL after the final adjustment as well. I only use a dedicated TC die when the crimp profile on my seating die doesn't give me the results I'm looking for. I use range brass for .45 acp and the case length varies a bit. My seat/crimp die has a bit more drastic taper and a case a few thousandths too long will receive too much crimp, one too short will get very little crimp. My dedicated TC die has a more gradual taper and all reasonable case lengths get an adequate crimp. __________________ Life Member NRA, TSRA Smokeless powder is a passing fad! -Steve Garbe I hate rude behavior in a man. I won't tolerate it. -Woodrow F. Call Lonesome Dove My favorite recipes start out with a handful of used wheelweights.

March 4, 2012, 08:12 PM	#10
IllinoisCoyoteHunter Senior Member Join Date: December 23, 2008 Location: Southern Illinois Posts: 1,527	I only SLIGHTLY "crimp" my .223 CAST boolits loads. The only reason I do this is because I have to slightly flare the brass mouth to avoid shaving lead when seating the boolit. I use a Lee FCD to just push the case mouth back flush against the boolit. Nothing more, nothing less. For all other jacketed rifle loads, I never crimp, whether running them through a semi or bolt rifle. __________________ ~~IllinoisCoyoteHunter~~ ~NRA LIFE MEMBER~ ~NRA CERTIFIED INSTRUCTOR~

March 5, 2012, 02:22 AM	#14
NWPilgrim Senior Member Join Date: September 29, 2008 Location: Oregon Posts: 2,346	Using a separate crimp die is especially useful when you are loading a lot of lead bullets. If I use a combination seat/crimp die it eventually gets clogged with lube and lead shaving and changes the seating depth gradually. I could periodically scrub out the seating die, or just use a separate crimp die. However, If I only seat in that die it does not scrape off as much lead and lube as when trying to crimp at the same time. I shoot mostly lead bullets in handguns calibers so all my handgun turrets are set up with four dies: sizing, expander/powder through, seat (with crimp disabled), and taper crimp (or roll crimp for revolvers). For rifle, most seating dies do not have built in crimping, so if you want to crimp for semi-auto use then you likely need a separate crimp die for it. Remember, whether you use taper crimp or FCD you only need to kiss the case mouth with it to remove the bell, unless you are roll crimping into a cannelure on revolver or rifle. __________________ "The ultimate authority ... resides in the people alone. ... The advantage of being armed, which the Americans possess over the people of almost every other nation ... forms a barrier against the enterprises of ambition." - James Madison

March 5, 2012, 03:42 AM	#16
NWPilgrim Senior Member Join Date: September 29, 2008 Location: Oregon Posts: 2,346	That may be your experience. Good for you. That is not a universal truth however. If you use one die and works well for you then great! Don't change anything. For myself, the lead bullets I can find at a good price have flecks of lube all over them. So just sliding into the case is going to scrape off some fleck of lube and after a few hundred rounds that adds up, even on the pistol cases. I have some other lead bullets that are very clean and do not do that but they cost 25% more than the other. There is no ONE way to reload. Everyone uses different component combinations and techniques for different purposes. There is absolutely nothing wrong with using a fourth die and at a one time cost of $10 per cartridge I find it worth being able to shoot 25% cheaper lead bullets for the next 30 years (God willing). I have recouped my cost many times over. And the extra time to pull through another die is made up for not having to remove, disassemble, clean, reassemble, install the seating dies every couple of hundred rounds. __________________ "The ultimate authority ... resides in the people alone. ... The advantage of being armed, which the Americans possess over the people of almost every other nation ... forms a barrier against the enterprises of ambition." - James Madison

March 5, 2012, 11:36 AM	#18
Hammerhead Senior Member Join Date: May 31, 2004 Location: Minnesota Posts: 2,432	I use a separate crimp die because I use a competition seater die that has no crimp ring in it. Bullet shaving is prevented by the case mouth flare and good bullet alignment. I do use a single seater/crimp die in .44 special and .45 Colt and don't get any shaving even with a solid roll crimp. It is possible to shave a lead or plated auto bullet if you have the crimp set too heavy because they have no crimp groove. Last edited by Hammerhead; March 5, 2012 at 11:42 AM.

March 4, 2012, 06:58 AM	#1
northwingnut Member Join Date: March 2, 2012 Posts: 27	Crimp or Not to Crimp I am very new to reloading and I started with my 10mm. I read a couple different manuals and they are all pretty vague about the type of crimp needed. On 10mm they say you can taper crimp if desired. I also want to reload .40 cal and the manual says no crimp is needed. Is that true or should I use a seperate factory crimp die for both?

March 4, 2012, 08:10 AM	#2
steve4102 Senior Member Join Date: December 23, 2005 Location: Minnesota Posts: 2,955	The crimp is a must if you want you loads to feed and function in a semi-auto. The crimp in these two rounds is called a "taper" crimp. You apply only enough crimp to remove the flare plus maybe a thou more. I crimp both my 40 and 10mm to .421.

March 4, 2012, 08:42 AM	#3
northwingnut Member Join Date: March 2, 2012 Posts: 27	So can I use the seating and crimping die to do both in one action or does that aply a roll crimp?

March 4, 2012, 08:48 AM	#4
IllinoisCoyoteHunter Senior Member Join Date: December 23, 2008 Location: Southern Illinois Posts: 1,527	Yes, use your seating die to both seat the bullet and taper crimp. The taper crimp, as stated, just pushes the flare back against the bullet. I decided to explain how to set up your third die so you can save money and not buy a dedicated crimp die. This is how I do it, if you care: 1. Put a case that has been sized and flared into the shell holder. Lower the handle on your press, which will raise the case to the top of the stroke. Then, screw the seating/crimp die into the press until you feel the crimping portion of the die contact the case mouth. Once this happens, back the die out one full turn. Tighten lock ring. 2. Make sure your bullet seating stem is backed almost all the way out. Put a bullet in the case and run it up into the die. At the top of the stroke, run your seating stem down untill you feel it contact the tip of the bullet. Lower ram and continue to screw in seating stem until you have seated the bullet to your desired COL (cartridge overall length). 3. Now, back your seating stem almost all the way out. Run the round back into the die. Loosen your die lock ring and screw the die body down untill you feel it come in contact with the case mouth (again...you did this in step #1). Once it comes in contact, you know that as you screw the die body down further, you will be applying more crimp. Keep screwing the die body down until you have achieved your desired amount of crimp. Once achieved, tighten die lock ring. 4. Run the round back up into the die and at the top of the stroke, screw in your seating stem until it comes in firm contact with the bullet. Now you can seat and crimp with the same die with no problems. Remember, the taper crimp just removes the flare. It should not dig into the side of the bullet. Hope this helps. __________________ ~~IllinoisCoyoteHunter~~ ~NRA LIFE MEMBER~ ~NRA CERTIFIED INSTRUCTOR~ Last edited by IllinoisCoyoteHunter; March 4, 2012 at 08:55 AM.

March 4, 2012, 10:42 AM	#6
primerman Senior Member Join Date: December 23, 2011 Posts: 153	To get a consistent crimp your cases should all be close to the same length.

March 4, 2012, 11:44 AM	#8
NESHOOTER Senior Member Join Date: October 16, 2009 Posts: 517	[QUOTE][Yes, use your seating die to both seat the bullet and taper crimp. The taper crimp, as stated, just pushes the flare back against the bullet. I decided to explain how to set up your third die so you can save money and not buy a dedicated crimp die. This is how I do it, if you care: 1. Put a case that has been sized and flared into the shell holder. Lower the handle on your press, which will raise the case to the top of the stroke. Then, screw the seating/crimp die into the press until you feel the crimping portion of the die contact the case mouth. Once this happens, back the die out one full turn. Tighten lock ring. 2. Make sure your bullet seating stem is backed almost all the way out. Put a bullet in the case and run it up into the die. At the top of the stroke, run your seating stem down untill you feel it contact the tip of the bullet. Lower ram and continue to screw in seating stem until you have seated the bullet to your desired COL (cartridge overall length). 3. Now, back your seating stem almost all the way out. Run the round back into the die. Loosen your die lock ring and screw the die body down untill you feel it come in contact with the case mouth (again...you did this in step #1). Once it comes in contact, you know that as you screw the die body down further, you will be applying more crimp. Keep screwing the die body down until you have achieved your desired amount of crimp. Once achieved, tighten die lock ring. 4. Run the round back up into the die and at the top of the stroke, screw in your seating stem until it comes in firm contact with the bullet. Now you can seat and crimp with the same die with no problems. Remember, the taper crimp just removes the flare. It should not dig into the side of the bullet. Hope this helps./QUOTE] I think you did very well explaining this die setup and the Lymans reloading handbook #49 states one can put a modest crimp as the .40,9mm, and little to no crimp on the .45. I use the Lee FCD and I do as ICH states then I can make the final ajustments to the crimp as I need/want.

March 4, 2012, 07:35 PM	#9
thedaddycat Senior Member Join Date: September 25, 2011 Posts: 388	ICH, very nice description on the adjustment procedure. That one's a keeper. Do you use the same procedure when doing bottleneck rifle cases that will be crimped? I have some sets of dies where I got the Lee Pacesetter dies (which come with the crimping seating die and a FCD) and then the Collet sizing die set to go with it. The Collet die set comes with what Lee calls a "Dead Length" seating die. This seating die will not crimp the case. Other chamberings I got the Deluxe Rifle die sets for. It comes with the FL and Collet sizing dies and a crimping seating die (not the DL seating die), but no FCD. I got a FCD for those chamberings. For some of my handloading I plan on just neck sizing fire formed brass for bolt action rifles, which do not require a crimp.

March 4, 2012, 08:59 PM	#11
northwingnut Member Join Date: March 2, 2012 Posts: 27	Thank you very much ICH. That is pretty simple and makes sense.

March 4, 2012, 11:49 PM	#12
Hammerhead Senior Member Join Date: May 31, 2004 Location: Minnesota Posts: 2,432	I use a separate Redding taper crimp die in 10mm and .40 to remove any trace of flare, no crimp is applied.

March 5, 2012, 01:05 AM	#13
northwingnut Member Join Date: March 2, 2012 Posts: 27	What is the point of using two dies? I have heard people say that it is somehow more accurate but I don't see why.