Seating and Crimping in the same stroke of the press.

[Stradawhovious]

Let me start by stating that I don't do this, as I use a Lee factory crimp die, and am really happy with it. I have tried and had no success other than seating a bullet into a crimp and causing issues. I have also not heard of anyone being able to reliably do this with 100% satisfaction.

What I'm referring to are the pistol die sets (specifically from Lee) that offer seating and crimping in one convenient step. Pull the handle, and your bullet is seated and your case is crimped. I have a friend that is set and determined that this can and should be done as per communication with Lee.

Has anyone, ever, throughout the course of history had satisfactory, reliable, repeatable, safe loads doing the seating and crimping in the same stage?

Discuss.

[Bessy]

Most of the dies I have seen that do the two in one step apply a roll crimp. I do have an rcbs die that does a taper crimp while seating. For revolver I think you could get away with the roll crimp while seating. The taper crimp seating die I have for rcbs is useless in that capacity... when loading lead or molly coated rounds it scrapes part of the moly, or lead off. Don't even think about using plated rounds with it. It might work for FMJ's though. I pulled out the seating part, I use it just as taper crimp die now.

My .02 cents is unless you are roll crimping for a revo, use a separate taper crimp die.

On a side note
I don't use the Lee factory crimp dies anymore with molly coated lead lead rounds, or copper plated rounds, as they can swage the bullet leading to accuracy/tumbling issues. The Lee factory crimp dies work well with fmj's. If you have to rely on the factory crimp dies to get reliable ammo, you probably have underlying issues with your dies setup or reloading procedure. If you have perfectly serviceable/reliable ammo using only taper crimp die, and apply the lee factory as a "just in case" die, then you are probably fine.

[Stradawhovious]

Sorry, I should have clarified. .45acp, taper not roll.

Thanks for the input B.

[Vlad]

I do seperate seat and crimp for everything but 44mag with Jacketed bullets.

[westhope]

I had problems with 9 mm reloads in my Springfield 9 mm EMP. (Factory ammo worked fine.)

I had been doing a taper crimp in a seperate die on a Dillon 650. No problems in other 9 mm's I have. I use range pick up brass of various brands.

What I found was the the RCBS sizing die (and I think most sizing dies) do not resize fully to the base. When I added the Lee Factory crimp die at the final stage, it resized just enough closer to the base for the reloads to chamber always. EMP's are known for tight chambers.

When rounds are fired in chambers that do not fully support the case, there is a slight bulge near the base of the case that does not get resized with a regular die. Someone (I can't remember who right now) makes a die that the case is pushed completely through. This will resize the case fully. There is also a resizing method that rolls the case between two plates (very expensive) that also corrects this problem.

I also use the Lee Factory Crimp die on may 45 ACP as an extra check at the end. I do use it with plated bullets, but I watch the crimp very carefully. Too much crimp on a plated bullet will cut through the plating and affect accuracy. Again, I use a varity of range pick-up brass for my 45 ACP.

[Bessy]

I had problems with 9 mm reloads in my Springfield 9 mm EMP. (Factory ammo worked fine.)

I had been doing a taper crimp in a seperate die on a Dillon 650. No problems in other 9 mm's I have. I use range pick up brass of various brands.

What I found was the the RCBS sizing die (and I think most sizing dies) do not resize fully to the base. When I added the Lee Factory crimp die at the final stage, it resized just enough closer to the base for the reloads to chamber always. EMP's are known for tight chambers.

When rounds are fired in chambers that do not fully support the case, there is a slight bulge near the base of the case that does not get resized with a regular die. Someone (I can't remember who right now) makes a die that the case is pushed completely through. This will resize the case fully. There is also a resizing method that rolls the case between two plates (very expensive) that also corrects this problem.

I also use the Lee Factory Crimp die on may 45 ACP as an extra check at the end. I do use it with plated bullets, but I watch the crimp very carefully. Too much crimp on a plated bullet will cut through the plating and affect accuracy. Again, I use a varity of range pick-up brass for my 45 ACP.

An undersized resizing die maybe helpful to you, if your brass is not getting resized correctly.

http://egw-guns.com/store/index.php?mai ... ucts_id=40

[westhope]

An undersized resizing die maybe helpful to you, if your brass is not getting resized correctly.

No, under magnification, I could see that the resizing die did not go down as far on the case as the Lee Factory Crimp die. Both dies were set to just touch the shell holder.

I know that Springfield will ream out the chamber of early EMP's if you send them back. My EMP has always worked fine with factory or my own reloads. (One exception was S&B 115 gr factory ammo. It would blow primers. I think this was due to soft primers on the S&B and the EMP having a titanium firing pin. All other factory ammo I have tried functions.)

[Bessy]

An undersized resizing die maybe helpful to you, if your brass is not getting resized correctly.

No, under magnification, I could see that the resizing die did not go down as far on the case as the Lee Factory Crimp die. Both dies were set to just touch the shell holder.

I know that Springfield will ream out the chamber of early EMP's if you send them back. My EMP has always worked fine with factory or my own reloads. (One exception was S&B 115 gr factory ammo. It would blow primers. I think this was due to soft primers on the S&B and the EMP having a titanium firing pin. All other factory ammo I have tried functions.)

Actually YES... the undersized dies have less of a radius on the mouth and re-size further down towards the base than standard dies which is why I suggested it (I do actually read what you post ). The one I have for my 45 does a better job than the lee factory dies in that aspect.

Except from product description "The EGW clearly resizes further down the case then the standard lee resizing die"

I've actually been through the exact problems you are describing (different gun, same issue tight chamber, with range brass)... this was how I ultimately fixed the issue, in a way that would let me use molly rounds, and not have them swagged by the lee factory crimp die.

[westhope]

I never have tried or looked at undersize dies. I have faced off a die to remove some of the radius at the entrance. This was a steel die for a straight wall 401 WSL rifle case and not on a carbide pistol case.

I was forming 401 WSL from 303 British.

[Sigfan220]

My RCBS 44mag die worked well with cast bullets and jacketed bullets with cannelure. The ones that gave me problems were the plated bullets. I had to be very careful not to overcrimp otherwise the case would bulge. Switched to the Lee factory crimp die as soon as the RL550 was bolted down...

[Seismic Sam]

Yes, I have managed to get my .440 Corbon Magnum seating/crimp die to work and yield the exact right COL and also crimp depth at the same time. It took me about three tries, and that's with 38 years of experience. This is something that you have to accomplish by getting the seating stem set within 1/8th of a turn of being rifht while also getting the die within 1/8th of a turn of being right in the press AFTER you have locked the die nut in place. Yeah, it takes practice.

[Big_R]

I've found that seating and crimping in one step works fine for jacketed bullets with a cannelure or cast bullets with a crimping groove.

Projectiles without these caused me problems with shaving, distortion, etc.

Ryan

[Seismic Sam]

I've found that seating and crimping in one step works fine for jacketed bullets with a cannelure or cast bullets with a crimping groove.

Projectiles without these caused me problems with shaving, distortion, etc.

Ryan

And that makes sense, because you can only do a ROLL crimp while the bullet is still moving into the case. Do this with a taper crimp, and the case mouth will start to cut into the bullet during its final seating. And of course, you can only do a roll crimp with a bullet with a cannelure, to allow the case mouth to move in that far.

[bensdad]

I use RCBS and Lee dies in a single-stage press (Rockchucker). Seat and crimp (taper) in the same stage all the time. 380acp, 9mm, 40s&w, 45acp. Pretty much just follow the instructions. Ya gotta fiddle with it more than the instructions let on.

[goalie]

Yes, I have managed to get my .440 Corbon Magnum seating/crimp die to work and yield the exact right COL and also crimp depth at the same time. It took me about three tries, and that's with 38 years of experience. This is something that you have to accomplish by getting the seating stem set within 1/8th of a turn of being rifht while also getting the die within 1/8th of a turn of being right in the press AFTER you have locked the die nut in place. Yeah, it takes practice.

Yup. I changed bullets for my 44mag and it was a PITA to get it all set up perfect again. I am leaning in the direction of getting a separate die to crimp with.