Just bought a 380 ACP for my wife. Plan to begin reloading for it.
Should I crimp the bullets?
For my 40S&W I do not crimp, and I have no problems with the rounds.
Any experience out there?

I use RCBS dies that come with a taper crimp sizer die for the .380. I put just enough taper crimp on the finished round to take out the bell and for the round to chamber easily. I am shooting a Ruger LCP and this works fine.

Never crimp any auto pistol cartridge. Never. they headspace on the mouth.
Taper crimp dies were made so they could just sell more dies; usually cause more problems than they solve, like loosening bullets.
All you need to do is make sure your brass flare is put back straight; not crimped inward. You can do that with the FL die, or yes, a taper crimp die.
But it is not actually a "crimp".
Sounds like you already know how to do it.

Thanks guys

I’ve taper crimped 1000s of 9mm and 45ACP and never had an issue.

No you don't need a crimp on .45/9mm/40. But you do need to get rid of the flare.

Problem with getting rid of the flare using a mixed function roll-crimp seating die is the crimping shoulder is too abrupt. Not a problem if you trim pistol brass.

Well I detest sorting and/or trimming .45/9mm. In fact I have never trimmed a .45 ACP brass case b/c they never reach trim length - at least not in my guns.

They are, however, apt to be any length between trim length and something more than that. When loading mixed brass a taper crimp reliably reverses the "bell" created by the expander station, and it does so without an undesired crimp on cases that are just a tiny bit longer than the rest.

So I don't mind the extra die.

quote:

Originally posted by df06:
I’ve taper crimped 1000s of 9mm and 45ACP and never had an issue.

Me tool. But I'll bet you, like me, didn't crimp the case mouth too much . . . meaning that you didn't affect the case's ability to headspace! I use my crimping dies only to remove the bell and have for countless thousands of 9mm, .380 and .45 ACP rounds. But I'm really careful to not overtrump. [EDIT: Not "overtrump" but "overcrimp." Doh!!! I don't know where "overtrump" came from in light of who I voted for and whose performance I am delighted with.]

Un-necessary? Probably. But I get wonderfully consistent cartridges and I'm unwilling to mess with a system that works so well.

People were successfully reloading for well over 100 years before the thing called a taper crimp die was invented.

quote:

Originally posted by dpcd:
People were successfully reloading for well over 100 years before the thing called a taper crimp die was invented.

Yep....and people were successfully going from the east coast to the west coast for 100 years via a horse and wagon.....geeeez

A taper crimp streamlines the case mouth for proper feeding and not hang up.

No taper crimp


Slight taper crimp


Below a RCBS .223/5.56 die with a taper crimp.



Below a .223 expander where the case mouth is bumped on to the .226 part of the expander. And the taper crimp is used to close up and streamling the case mouth for proper feeding.



Handgun Cartridge Crimping
http://www.massreloading.com/H...tridge_Crimping.html

Taper Crimping
Unlike a roll crimp, a taper crimp does not leave a radiused edge on the case mouth. A taper crimp simply flattens out the 'belling' that was previously done by the expander die, and squeezes the case mouth tightly against (but still mostly parallel to) the sides of the bullet. A taper crimp leaves a distinct 'step' at the top edge of the case mouth.

When Should a Taper Crimp Be Used?
A taper crimp should be used for any rimless straight-walled or tapered case (like the 9mm, .40 S&W, .45 ACP, etc) because these cartridges headspace on the case mouth. If a roll crimp is used on any of these (or other rimless straight-walled cartridges), the round will not properly headspace in the chamber. Instead, it will likely headspace on the extractor. If conditions are just right - or wrong depending on how you look at it - a cartridge of this type with either a roll crimp or too much taper crimp can fire with the case mouth pushed into the rifling. This will cause an extreme pressure spike which can result in catastrophic failure of the cartridge case and the firearm.

Note that there is no reason why you can't apply a taper crimp to a bullet with a cannelure or crimp groove, however, the bullet does not need to have either of these features in order for a taper crimp to be used.

Taper Crimp: Everything you need to know (Read 22603 times)
https://czfirearms.us/index.php?topic=78873.0

Fig. A: Missing Taper Crimp on a Straight Walled Cartridge Case

Still.. Note that word, "Successfully", meaning, functions perfectly.
The horse analogy is invalid. That implies that in order to be successful (fast), you have to use a taper crimp die. Nonsense.
If you feel you need one, then by all means, use it. Why belittle me because I don't need them?
I never owned one, nor used one.
Never had any problems with any of my reloaded pistol ammo.
And that is many thousands, for the past 50 years.
So, each one draws his own conclusions, as they see fit, with various reloading techniques.
I am giving the OP another data point to consider.

I wonder why pistol dies come with a taper crimp die.

And I wonder why everyone doesn't just use their sizing die to compress the case mouth flair.

Although I have every one under the suns dies,+ although I LOVE RCBS,buy the Dillon dies;they cost more but you will never look back.The Q/D case mouth opener is worth the set of the dies.Until you buy a set you can't fully appreciate what I mean.

Should not the bullet seating die flatten out the case mouth flare. My RCBS 404J die does this perfectly when flaring for cast bullet seating as does my Lyman 7mm-08 bullet seating die, both when using several different brands of cases?
Or did I just get lucky?

generally you don't need to crimp loads for autos.. if however you are experiencing feed problems, or a some that don't seem to want to chamber easily, or some that get set back into the case, then get yourself a TAPER CRIMP die.. I use that with my 45's and never have an ammo related feed or chambering problem.

I load for .460 Rowland. I believe the crimp is necessary. Also I believe that .50 AE and another high power / high kick rounds need crimp. I crimp in a separate step.

Jiri

Two schools of thought here, both are right if done correctly..not much of an argument.