Taper crimp die vs Factory Crimp die

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I have been having some issues with my 40 cal in my M&P. I was going to try a Lee FCD but I have found out that there is also a Taper crimp die. What is the difference? I was trying to use my Lee bullet seat and crimp die to crimp along with seating the bullet but I think I'll just use that to seat bullet and use the FCD (or taper crimp). Help, I'm confused!
 
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I have been having some issues with my 40 cal in my M&P. I was going to try a Lee FCD but I have found out that there is also a Taper crimp die. What is the difference? I was trying to use my Lee bullet seat and crimp die to crimp along with seating the bullet but I think I'll just use that to seat bullet and use the FCD (or taper crimp). Help, I'm confused!

The 40 S&W requires a taper crimp since it headspaces off the mouth of the case like the 45 ACP and 9mm among others. I would expect the Lee factory crimp die for the 40 to be a taper design.
 
The 40 S&W requires a taper crimp since it headspaces off the mouth of the case like the 45 ACP and 9mm among others. I would expect the Lee factory crimp die for the 40 to be a taper design.


True, but the FCD goes farther than just crimping. It also sizes the loaded round back down to minimum SAMI specs. I use the FCD on every thing I reload. Sometimes when crimping with a standard crimp die, it can leave a slight bulge in the case, below the crimp.

EarlFH
 
Lee dies taper crimp for semi auto cartridges. They roll crimp for revolvers.

The LFCD does the same plus it post sizes the whole brass.

So, the FCD for the 40 SW will taper crimp and post size.

I use the FCD on everything I load.
 
I use the FCD on all the auto ctgs, .45, 9mm,10mm,.40. For .38/.357. I don't use the FCD. In some cases the FCD will swage the bullet to a smaller size than I want and create a leading situation. However, again I think it's a fine idea for the pistol rounds.
 
I have been having some issues with my 40 cal in my M&P. I was going to try a Lee FCD but I have found out that there is also a Taper crimp die.

If you aren't aware of a taper crimp die, how are you currently closing the flare you created prior to seating the bullet?

During sizing are you eliminating the bulge near the rim of the brass? One way to check is to remove the barrel from your pistol and drop the sized brass into the chamber. It should make a resounding "clunk" as the brass bottoms in the chamber.

The 40 is notorious for swelling the base of the brass. Generally due to generous chambers on some pistols. The type and adjustment of your sizing die may or may not be adequately sizing the brass, to allow it to fit into your chamber.

So I would suggest you check for proper sizing of your brass, use just enough flare to allow bullet seating, and close the flare in a separate step from bullet seating. A cartridge gauge can be useful in checking to determine your techniques are proper.

I'm not saying not to use a FCD, just make sure you know what you are tying to accomplish with it.
 
The issue I am having is where the round gets stuck on the ramp and the slide won't go all the way forward. If I pull back the slide and release the round will then chamber.
 
Does it do this with all of your magazines, or just one? Magazines are one of the things that cause problems with autoloaders not feeding correctly. The overall length of the cartridges can cause feeding problems. Be sure to make them the exact same length that is recommended in the reloading manual. Using a cartridge length guage, will tell you if your rounds are sized correctly. if it won't drop into the length guage without help, it's not sized correctly. Auto loaders are very finicky about size, and loading pressures.

EarlFH
 
Didn't get an answer about how the OP was crimping prior to looking at a taper crimp or a Lee FCD?
I would guess, and it is only a guess, that the OP was seating the bullet and crimping in the same step. This can cause some case/bullet/COL/crimp to conflict and it could put a bulge in the case.
It is always best to separate the two actions.
Next, if using jacketed bullets and cases that have a nich chamfer, it is possible to seat the bullets without having any flare/bell on the case mouth. This also can cause problems with come combination of components.
If your case are sized properly and you have sufficient case mouth flare and your expander has increased the case ID to 0.001-0.002" less than bullet diameter, the Lee FCD will not even touch the case with the carbide insert. It just touches any part of the case that exceeds SAAMI max case diameter.
In many cases (particularly hot 9x19 and .40S&W), the fired case will have a slight bulge. This bulge can cause a raised ridge to form down near the extractor groove of the case and cause a failure to chamber. The best solution to this is, if you notice this ridge, to run your cases through the Lee Bulge Buster so the ridge never has a chance to form.
Also, if you can easily feel or see the case bulge, that case has been weakened enough that I dispose of them.
Lee makes an excellent taper crimp die, along with their FCD.
 
Are you using virgin brass? If using brass fired from a Glock there could be feeding problems
 
The issue I am having is where the round gets stuck on the ramp and the slide won't go all the way forward. If I pull back the slide and release the round will then chamber.


OK, what bullet are you using and what is you OAL of the finished round?

M&P's are not too fussy, they should feed just about anything. Is the gun and magazines pretty new? As mention Mag springs can be a problem, but without more info, hard to say.

Lead, FMJ, HP weight etc.

DATA DATA we must have DATA.:D;)
 
DATA DATA we must have DATA

Here is the data:
Used brass; 155 grain plated bullet; 4.2 grain W231; 1.120" oal; CCI small pistol primer; Lee reloading die, 3 die set; seat and crimp at same time. 98% sure I don't have any glockenspeil fired brass. I have 6 mags and they are about 2yrs old with hundreds of round thru each one. No, I have not traced the problem to a particular mag. Lets see, anything else? I also reload a 9mm with a 4 die set and have not experienced the problems I am having with my 40. I don't seat and crimp with that setup I seat and them crimp with 4th die. Thanks for all your responses so far!
 
Flat nose or round nose bullet?:) Berry, Rainer?

Your OAL is fine. It's kind of tricky seating the bullet and crimping at the same stage as sometimes when you turn the die in to add a crimp it seats the bullet a little lower.. Do you have the Lee Manual? On page 75 he explains exactly how to set the die. Much better than the instructions that come with the dies. If you do not have the manual. let me know and I will send you the part from the book.

Actually if you do not flare the case too much the bullet should seat and not need much of a crimp anyway.

The flare should just let you barely get the bullet started.

Are you trying to feed the rounds manually or does this happen when shooting?. You can not really duplicate feeding problems manually with dummy rounds.

A picture would help if you can post one.

EDIT: I just checked some of mine. I seat 165 plated FN at 1.125 using either 5.5 or 6.0 gr HP 38
 
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About that post resizing, I have yet to come across one of my reloads that was actually resized by the FCD even though I use one on all my handgun reloads. I think you are doing more wrong that you think if it comes to that... (although it is a good "safety net")
 
About that post resizing, I have yet to come across one of my reloads that was actually resized by the FCD even though I use one on all my handgun reloads. I think you are doing more wrong that you think if it comes to that... (although it is a good "safety net")

I agree, I pretty much use it just to crimp. Once and a while you can feel it a little tighter on the case so I guess it's doing something. As Mr Lee says in the manual, you will not feel it touch every case.

I did have some 357 Mags that I loaded to deep and it was crimping past the cannelure. They would not fit in the cylinder. I ran them through the FCD and it made them fit.:)
Must have smashed the lead in just enough.
 
Lees site says a "taper crimp die" is only needed for dies older than 1985 or so. Any newer carbide dies set shouldn't require the use of a FCD unless the dies are not set up properly.
 
Lees site says a "taper crimp die" is only needed for dies older than 1985 or so. Any newer carbide dies set shouldn't require the use of a FCD unless the dies are not set up properly.

A taper crimp die is not the same as a FCD!!!

If you don't want to use it, then DON'T.

I'm sure that Lee only makes them by the thousands, for dumb a..'s like me, who swear by them.

EarlFH
 

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