Factory crimp die needed for 380

BondoBob

New member
I’m considering the Lee 3 die set vs the 4 die set for 380. I’ll be using Berry’s plated 90, 95 and 100 gr bullets. Is it necessary to have the factory crimp die? I realize it is optional on some cartridges. Does the seater die also double as a taper crimp with the 3 die set? The description doesn’t explicitly say that. I’m comfortable doing the setup for seating and crimping on 1 die, but not sure if it’s ok w plated bullets.
Thanks.
 
Yes, pretty much all straight wall rimless seat dies also taper crimp. Factory crimp dies are not necessary. If used wrong, they can actually swage the bullet diameter down

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I always order the Lee 4 die set. I own multiple handguns in the same cartridge, so its a nice die to use to ensure that the rounds will chamber in all my handguns
 
I own multiple handguns in the same cartridge, so its a nice die to use to ensure that the rounds will chamber in all my handguns

So, how does it do that? How is it different then the crimp from the bullet seating die? If it's just more convenient I'm ok doing both adjustments on 1 die. But if there's an outcome that is different, I'd like to know.

Thanks,
 
The 4th die is also a carbide sizing die, it assists in making sure every round is within the specs for that cartridge.

Snip from the Lee site:
"A carbide sizer inside the Carbide Factory Crimp die post-sizes the cartridge while it is crimped so every round will positively chamber freely with factory-like dependability. The adjusting 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. A firm crimp is essential for dependable and accurate ammunition. It eliminates the problems of poor ignition of slow burning magnum powders."
 
Is it necessary to have the factory crimp die?

No.

I've been loading since the early 70s without one and my ammo works just fine in the guns I have, including multiple guns in the same calibers.

The Lee factory crimp die may be a good tool, I don't know, never used one. Some people say it works wonders. I've always thought it was a solution to a problem that doesn't exist.
 
The Lee factory crimp die may be a good tool, I don't know, never used one. Some people say it works wonders. I've always thought it was a solution to a problem that doesn't exist.

I couldn't agree more, especially with the last statement. I think it more covers up improper die setup. There could be a small number of limited situations where it's needed, but I have never run into one. So I don't know.

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I have the Lee 4-die carbide set for all my pistol rounds. Never had a problem with the FCD. I believe the FCD is the most controversial piece of reloading equipment.:)
 
Another option, if you’re just looking to take the bell out of the case (proper straight wall semi-auto crimp) and you have a 9mm die, just use it. Properly set up, of course.

A review of my Hornady dies indicated the only difference between the .380ACP set and the 9mm Luger set is the sizing die. Expander, Crimp, Seater....all the same since the mouth of .380ACP and mouth of 9mm Luger are the same. At least I got 2 boxes of “free bullets” by buying separate die sets.
 
markr6754 said:
Another option, if you’re just looking to take the bell out of the case (proper straight wall semi-auto crimp) and you have a 9mm die, just use it. Properly set up, of course.

A review of my Hornady dies indicated the only difference between the .380ACP set and the 9mm Luger set is the sizing die. Expander, Crimp, Seater....all the same since the mouth of .380ACP and mouth of 9mm Luger are the same. At least I got 2 boxes of “free bullets” by buying separate die sets.
But they aren't the same ... or, if they are, they shouldn't be.

Per SAAMI, .380 ACP should have a case OD of .3730 at the mouth, and .3731 at .04" back from the mouth. 9mm should have an OD of .3800 at the mouth and .3811 at .04 back from the mouth. That difference of .007 could mean the difference between chambering properly, or not chambering properly.
 
These days I always get the Lee 4 die set. I shoot a lot of cast bullets in my revolvers, and occasionally I’ll have trouble chambering a reload. The FCD fixes that. I can’t remember having any chambering issues with jacketed or plated bullets.

I find it interesting that people get so worked over the FCD die. Having one does not mean your reloading is suspect. Of course, neither does it mean that your reloading is not suspect.

My use of the FCD is almost always limited to the 357 and those cast bullets.I have come to believe that some of the 357 cases are a touch too long (I shoot mixed brass, new and old), which rolls the crimp a bit more than necessary, and causes the chambering problem.
 
It seems to work better on any Semi round to taper crimp AFTER seating the bullet. If Not, you are pushing the bullet deeper into the case (Or flattening the bullet nose) while crimping. Ask me how I know this.............
 
A review of my Hornady dies indicated the only difference between the .380ACP set and the 9mm Luger set is the sizing die. Expander, Crimp, Seater....all the same since the mouth of .380ACP and mouth of 9mm Luger are the same.

I'd say who ever reviewed your dies needs to be reviewed.

Not only is the case mouth a different size, the 9mm case tapers to .391" at the case head, while the .380's widest point is the rim at .374" And, there is 0.74" difference in the case LENGTH as well.

This won't matter to an expander die, since all they are is a wide open die body to hold the expander stem, but it DOES matter to a seating die. Especially the length.
 
The expander die and a seating die with no crimp, like the Dillon dies, can be made to match due to using the same bullet diameter and bullet nose shapes, but the sizing die and the crimp die may differ. The Lee Carbide Factory Crimp Die will certainly differ at its carbide ring.
 
Do we assume that a seater die, with no crimp, is still made to remove case mouth flare, and return the brass to its proper spec (or slightly under) ???

If this is the case, then I would think the nominal .007" difference between the 9mm and .380 case mouths would be an issue.

I'm probably out of the loop, since all my pistol dies (with one exception, the .44AMP) have a built in crimp in the seater die. I even have old .45ACP die that does a roll crimp! (for the .45 Auto Rim, but also usable with ACP brass)

I would think that a 9mm seater die wouldn't "unflared" a .380 case enough, especially since the .380 is not only smaller in diameter but also shorter, and so wouldn't get the full "squeeze" a 9mm die is capable of, and a .380 die would squeeze a 9mm too much.

I once loaded .38 Super brass in .38 Special dies. The Super brass got squeezed down more than needed, and it wasn't "right" but the ammo did function and fire ok. Sometimes, there can be a difference between what's right, and what works.
 
A word of warning if buying a Lee .380 die set. Odds are before you are done you will need their "undersized" sizing die in order to obtain sufficient neck tension to prevent bullet setback. Few years back I bought my two sons .380 LCPs for Christmas. They asked me to reload for them and since I didn;t already reload .380 and did not intend to reload a lot of .380, I thought I'd save a few bucks and get Lee dies instead of the more expensive RCBS. After the first 100 or so I noticed bullet setback and tried a few things like flaring as little as possible. What I found was, that after resizing I did not need to flare at all to get the bullet to start in the case. When I contacted Lee, they said they "knew" they had an issue with their standard .380 sizing die with "certain" brands of brass. For me, it was with all types of brass, including the thickest, Starline. Their solution? Buy their "undersized" die for $29 plus $8 shipping. In the end it cost me more for the Lee dies than it would have for RCBS. I don't know why, if they know they have an issue with their standard .380 they just don't fix the problem instead of making you buy another die that cost as much as their standard 4 die set. I have since seen multiple threads and posts about others having this same problem....but only with Lee dies. With the "undersized" die, I now have plenty of neck tension regardless of brass. My beef is, that I had to buy it in the first place.
 
When I contacted Lee, they said they "knew" they had an issue with their standard .380 sizing die with "certain" brands of brass.

Wow! Thanks for mentioning that Buck. I just cancelled my order for Lee dies with Midway until I do some more research on this.

I wonder would the Lee dies be ok without the undersized if using 356 bullets. Were you using 355 dia bullets Buck?
 
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I have all Lee dies except for .223 which is a RCBS set-and still use a Lee FCD.
I reload .380-9mm-.40S&W-.45ACP-.357 Mag-.41 Mag-300AAC and all these are Lee in either the 3 or 4 die set's.
I have never had a problem with any Lee die's.
 
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