Lee Factory Crimp Die

[brigond]

I have the lfcd on my turret press. I was researching what the crimp die does and how much crimp is too much. I found info about how to tell if you have too Much crimp but only on FMJ. What about a lead bullet? I bet almost any crimp will dig into a lead bullet. I'm using a harder #18 lead bullet.

[tkglazie]

Totally depends on the caliber. For something like a .38/.357 the FCD uses a roll crimp. For a 9mm, for example, it uses a taper crimp.

When using an FCD on lead bullets your issues will be with the ID of the post-sizing ring more than the crimp. If you happen to have a tight FCD you will be swaging your lead bullets down. There is a recently closed thread that has a lot of good info on the subject. One member has measured his .45acp FCD at .470" for example. Mine is .471-.4715 and only slightly swages my .452 lead when using stand .010" wall thickness brass. )

In other calibers, like .380, .38, .357 and 9mm, my FCDs are the perfect size to use with lead bulelts without any swaging at all.

[brigond]

Thanks, I'm going to make a few inert bullets with different crimps. I'll pull the bullets and choose the crimp that least damages the bullet. Than I can take a I'D measurement also. I'm using 9mm. Is that closed thread still readable ? If so, do you remember the title so I can scan through the old threads to find it.

[tkglazie]

http://thefiringline.com/forums/showthread.php?t=504532

[CrustyFN]

What TK said. My fcd in 45 auto measures .472 and never swages any of my bullets. Like TK said check to see if you got a good one. It looks like Lee needs to get a lot better with their quality control on the post sizing rings.

[brigond]

Thank you much for the link.

[BDS-THR]

My comment is for straight walled semi-auto pistol caliber FCD use only, like 45ACP/40S&W/9mm. As to needing FCD to "fix" finished rounds so they'll feed/chamber reliably in tighter match barrel chambers, I load for tight chambered Sig 1911 and Lone Wolf barrels and do not use FCD. I also seat and taper crimp in one step.

As verified by Lee Precision (see email quote below), FCD was meant to be used as a "finishing die" with jacketed diameter bullets to ensure finished rounds would reliably feed/chamber in SAAMI spec barrels/chambers. Why use a finishing die? Depending on the bullet manufacturer/QC, bullets you use may be "out of round" and finished rounds' outside dimensions may not allow reliable feeding/chambering in SAAMI spec chambers. FCD's carbide sizing ring will help these out-of-spec rounds. I use Winchester, Remington, Montana Gold jacketed bullets and Speer Gold Dot plated bullets and do not need to use the FCD as rounds coming out of my Lee combination seater/taper crimp die feed/chamber reliably in all of my pistols, even in tight chambered Sig 1911/Lone Wolf barrels.

Also verified by Lee Precision, I do not recommend the use of FCD with larger than jacketed diameter lead bullets as the carbide sizing ring may post-size the diameter of the bullet decreasing bullet-to-barrel fit and increasing gas cutting/leading. If the post-sizing of the bullet and brass case wall spring back occurs, you may experience decreased neck tension and if you feel the FCD post-sizing your finished cases, I would check the OAL before and after manually feeding a test round from the magazine.

If you want to seat and taper crimp in separate steps to avoid shaving of the bullet side without post-sizing, you can always buy a separate taper crimp die (around $10) or have Lee Precision increase the diameter of the carbide sizer ring of the FCD.

This is from John Lee, President of Lee Precision on the use of FCD for straight walled semi-auto pistol cases:

From: "John Lee" <[email protected]>
Subject: Re: Factory Crimp Die for lead semi-auto calibers
To: "XXX" <[email protected]>
Date: Thursday, October 13, 2011, 11:26 AM

Thanks for the suggestion of a Factory Crimp die with an interchangeable sizing ring. I will think about your suggestion but have serious reservations about producing it and calling it a Factory Crimp die. If we make the sizing ring any larger it will not produce ammunition that will work in any firearm.

I guess we could advertise it as "Produces ammunition that may work in some firearms"

Seriously, the sizer ring is .001 to .002 smaller than a SAAMI maximum cartridge. This produces a finished cartridge that will not exceed Factory Maximum, a dimension necessary to fit in any standard chamber gun. Many users can use larger cast bullets that swell the case in excess of factory maximum and will work perfectly in one or more of their guns. That same crowd frequently will use a taper crimp die to assure "reliable feeding". The taper crimp die nicely squeezes the brass in turn reducing the bullet shank diameter. Had they used the correct diameter bullet they would not have needed a taper crimp die nor a Factory Crimp die.

For any given brass thickness there is a limit on how large your bullet can be and not swell the brass over the SAAMI limit. If you are using selected brass of uniform wall thickness one can successfully use larger cast bullets without fear of producing ammo that will not chamber properly in any gun. If you are using mixed range brass stick with the bullet diameter that the cartridge was originally designed for and you won't need a taper crimp die nor a Factory Crimp die.

Again thank you for the suggestion for a "screw adjustable crimping die" basically our Factory crimp die without the sizing ring, it would be a fraction of the cost of Factory Crimp die without the ground and polished carbide ring. Bounce the idea off your friends on the forums and if there is much interest I will give it serious consideration.


Sincerely,

John Lee, President

This is from Dardas Cast Bullets regarding the use of FCD - https://www.dardascastbullets.com/mm...re_Code=dardas

Please do not use factory crimp dies for cast bullet reloading. Cast bullets MUST remain in their pristine state in order to shoot accurately. Factory Crimp Dies will decrease the cast bullet's sized diameter and thus will cause many unwanted issues.

This is from Precision Bullets FAQ page regarding their Moly coated bullets and the use of FCD (scroll down to Reloading Tips and Troubleshooting):

Do not use a roll crimp or Lee Factory Taper Crimp Dies.
The roll crimp will cut through the coating. You must use a taper crimp die.
The Lee Factory Taper Crimp Die will undersize the bullets causing accuracy and fouling problems.

If you are using the Lee Factory Taper Crimp Die, try switching to a standard taper crimp die ... Slug your bore, oversized bores will foul heavily and be inaccurate.

[tkglazie]

Good info.

[Edward429451]

Biy, that John Lee sure is a cynical cuss aint he? Poor guy, think of all the frustrated customers he has to talk to.

Also verified by Lee Precision, I do not recommend the use of FCD with larger than jacketed diameter lead bullets as the carbide sizing ring may post-size the diameter of the bullet decreasing bullet-to-barrel fit and increasing gas cutting/leading. If the post-sizing of the bullet and brass case wall spring back occurs, you may experience decreased neck tension and if you feel the FCD post-sizing your finished cases, I would check the OAL before and after manually feeding a test round from the magazine.

So the FCD is not for any lead boolits. I knew this but it's kind of nice to see them admit it in print, lol. Actually I don't mean to slam too hard on ol John, I do like the crimp the FCD makes once I popped out the sizing ring. It worked well with the size ring on jacketed bullets, and the rifle cripm die works good also.

[CrustyFN]

So the FCD is not for any lead boolits.

It is if it's the right size. I use a FCD in 9mm, 38/357 and 45 auto. I don't have a problem with jacketed or lead. That's the problem, not all FCD's are made to the same spec.

[wncchester]

"I do not recommend the use of FCD with larger than jacketed diameter lead bullets".... "So the FCD is not for any lead boolits. I knew this but it's kind of nice to see them admit it in print, lol."

That isn't what the man said. And there is no logical reason to use over sized cast bullets in anything unless the bore is sloppy oversized.

[BDS-THR]

Keep in mind that my post was for straight walled semi-auto pistol caliber FCD as FCD for revolver/rifle are different.

Originally Posted by BDS-THR

My comment is for straight walled semi-auto pistol caliber FCD use only

The email I sent to the president of Lee Precision and his response were specific of FCD for semi-auto calibers.

Originally Posted by BDS-THR

This is from John Lee, President of Lee Precision on the use of FCD for straight walled semi-auto pistol cases:

I was suggesting that Lee Precision consider a FCD with threaded removable carbide sizer like in their discontinued "speed dies"
(blue arrow in the picture).



But of course, this would mean a significant tooling/added cost of production and this was John Lee's response:

Thanks for the suggestion of a Factory Crimp die with an interchangeable sizing ring. I will think about your suggestion ... a "screw adjustable crimping die" basically our Factory crimp die without the sizing ring, it would be a fraction of the cost of Factory Crimp die without the ground and polished carbide ring. Bounce the idea off your friends on the forums and if there is much interest I will give it serious consideration.

Although I do not need to use the FCD for straight walled semi-auto pistol cases on a routine basis, I do consider it a beneficial tool to have as a "finishing die" to fix sometimes inconsistent finished rounds' dimensions often from out-of-round bullets or out of spec bullets.

If you want to use it for larger diameter lead bullet without post-sizing the bullet that may reduce neck tension, bullet-to-barrel fit and increase gas cutting/leading, you can order the FCD with enlarged carbide sizer ring or have your FCD modified by Lee Precision (I believe they charge $15 for the service).

My suggestion was to use the body of the discontinued "speed die" as a taper crimp die with removable carbide sizer rings so I could use the same die body for both jacketed and lead diameter bullets instead of having two FCDs with different carbide sizer rings.

Will Lee precision consider making such a product? If they did, it would sure put an end to never-ending FCD threads as the "FCD with removable carbide sizer" will address both jacketed and lead bullet diameter concerns.

[Edward429451]

That isn't what the man said. And there is no logical reason to use over sized cast bullets in anything unless the bore is sloppy oversized.

Uh, ok.

[rodfac]

As a general rule, I use the least crimp possible in order to secure the bullet during feed and recoil. I'd use none if it were possible. Crimping on lead alloy bullets distorts them as the case opens the crimp...use as little as you can get away with. In .45 ACP, I use a spare sizing die as a taper crimper, after the bullet is seated to the desired OAL.

As to "oversize bores" etc, in a revolver, a lead alloy bullet needs to fit the cylinder throats, with the bore being smaller. The reverse (bore is bigger than the cylinder throats) will destroy real accuracy with cast bullets. As a general rule, I size mine .001" over cylinder throat diameter.

You can find out what you need by forcing a pure lead round ball through your throats, comparing each to its mates. Then do the same with your barrel. It should be smaller by a small amt....001" is about ideal in my experience. Cylindersmith.com can hone your cylinder throats to an even dimension with superb results. I've done two Ruger .45's with under size throats and halved their group sizes with cast bullets.

For an automatic, size your bullets (lead alloy), .001" over groove diameter. I.E. for a .45 ACP with a .452" groove dia., I'd size my lead alloy bullets, ideally, to .453. With relatively good alloy, in reality, .452" works just fine.

Best Regards, Rod