Crimp problem with .380ACP

[exavid]

Lately I've been having a problem with the crimps on .380s fired in my LCP. Apparently the jolt of firing is forcing bullets in the magazine deeper in the cartridge. This results in the edge of the case catching in the chamber and preventing the slide from locking in battery. Anyone else have a problem like this and what's the cure? I've got the Lee seating/crimp die run down until it touches the ram on the press and setting the OAL of the loaded shells to the recommended length in the Lee .380 die manual for the bullet I'm using.

 

[Mobuck]

Either grind some off the bottom of the die or get a separate taper crimp die. Having bullets set back into the case can be very bad possibly blowing up the pistol.
If you're crimping at all, the case should not "catch in the chamber". Do you mean the mouth of the case is catching the back edge of the chamber? I've been able to get half the thickness of the case mouth crimped with the LEE taper crimp die. Much more than this and headspacing may be compromised. You may be overcrimping causing the case to actually swell behind the crimp resulting in bullet setback and failure to chamber fully.

 

[Iron Mike Golf]

I have had problems with the case bulging when seating with some headstamps (Win and Fed come to mind). I think it's due to a thicker case wall. The bulge occurs just behind the bullet and my PK 380 hangs up 1/8 inch short of battery. You can see photo examples of this in the June 2010 issue of Handloader magazine in the article "Loads for Little Pistols".

I fixed that by using a Lee Factory Crimp Die.

 

[exavid]

Thanks for the responses, as you'd expect it was a cockpit problem. I'd set the bullet seating/crimp die as per Lee instructions but when looking closely at some of the problem cartridges and the turret press it occured to me that there's just a bit of lift of the turret plate when the ram comes up. There has to be some play or the plate couldn't turn. I measured it as .003". That was just enough to cause the crimp to be nearly nonexistant. With a bit of adjustment it now works as it should. I just finished re-crimping a hundred rounds of .380 which now feed as they should. This never came up before for me, previously my presses were single stage and since I got the turret press the other two cartridges I load are 9mm and .40S&W which are four die sets instead of the three die sets. It's a lot simpler adjusting the separate seating and crimp dies compared to the combination seat/crimp types.

 

[MADISON]

Two things to consider:
A TAPER CRIMP should be used.
Take a round on a very solid serface. Try to push the nose of the bullet
through the serface. If the bullet does not move, you have enough crimp.

 

[DeletedMember275]

I would take a different approach and increase my neck tension. You can reduce the diameter of the expander plug, or buy a .001" undersize sizing die from EGW to do it. Increasing the amount of taper crimp may or may not solve your problem. It can also induce other problems by swaging your bullets down as they're crimped in place.

A tightly crimped, loose bullet is STILL loose!

 

[44shootist]

I would toss the cheep Lee dies and try some good RCBS, or Lyman dies I think that will solve your problem, if not both companys will bend over backwards helping you make them work right.