45 ACP crimp problem

[50GI Jess]

Hi all,
No matter what brand of crimping die, or amount of crimp used, I can't seem to make plated 230's stay put in the casing. There's a bullet jump of app. 30/1000, when shooting them in my S&W 625 with a power factor of 172 for IPSC !

Anyone had this same problem ? Is it the slick surface of the bullet ? Lead, coated and FMJ works fine for me, and I'll have to go back to them, because I simply can't fix this problem.
Jess

 

[50GI Jess]

uuup's sorry !
Posted in the wrong thread.

 

[1911user]

I'd check if the plated bullets were undersize. If that is OK, I'd check if the sizing die is resizing the brass enough.

With a rimless case, the bullet is held in place by tension between the case and bullet, not how much you crimp it. This isn't a roll crimp like you'd apply to traditional revolver (rimmed brass) rounds. An ideal rimless case crimp is simply removing the belling from the expander stage.

On a plated bullet, the lead is relatively soft. So each time you try to crimp it "harder" the case and bullet are squeezed down in size a bit. The brass case springs back, but the soft lead does not. Really tight crimps are probably making your problem worse. This is also the reason I have no use for plated bullets when bulk FMJ cost only slightly more. If there was a big price difference, it might be worth the reloading effort and time to come up with a plated bullet load that works for you.

 

[50GI Jess]

Very good points 1911user,
I may try an U-sizer die also, even though the one I'm using now, will hold everything else in place but plated bullets. Thanks for the input.
Jess

 

[streetglideok]

I use the Lee carbide dies with the factory crimp die. The crimp die is to taper crimp 0.470" at the case mouth. Havent had any setback problems here with lead or jacketed.

 

[Shadowrider]

What kind of sizing dies are you using? What dia. is your expander plug?

 

[1911user]

Very good points 1911user,
I may try an U-sizer die also, even though the one I'm using now, will hold everything else in place but plated bullets. Thanks for the input.
Jess

I use a U-die for 9mm because a certain brand/lot of (thin) brass cases and normal FMJ bullets were causing setback issues. That isn't good using titegroup powder. If I was to load lead 9mm bullets, I'd go back to the normal sizer die. For anything 9mm jacketed, I consider the U-die as good insurance.

For shooting a 45acp revolver at matches, a u-die sounds like a very good idea.

 

[criticalbass]

I use the Lee carbide dies with the factory crimp die. The crimp die is to taper crimp 0.470" at the case mouth. Havent had any setback problems here with lead or jacketed.

Me too. When it comes to crimping, Lee has this die and the one for rifle ammo, and both of them have the edge on about everyone else. CB