45 acp, crimping

[Hefights]

Get an RCBS or Lee taper crimp die and use it for the last step, follow the instructions, it will be good. The case headspaces on the mouth as stated previously. Crimp just enough for the mouth to to be snug to the bullet with case mouth still having that easy to feel "edge" all around the bullet, i.e. don't overcrimp the mouth into the lead.

[gatorbone]

Thanks to all for the sage advice, Ill double check my dies (Lyman) and see for sure what I have. Invest a few bullets and cases to see whats actually happening.

Thanks again.

[da gimp]

might mike the expander plug on your decapping rod, a very few slip thru quality control that are over sized...........also mike your bullets & make sure that they aren't undersized, some lead alloys shrink quite a bit as the bullet cools after they are dropped from the mold.......sorry I didn't think of this before.Lyman makes daam good dies too.

[DaveL]

I've been loading 45 ACP for 40 years. I never owned a taper crimp die. Every standard bullet-seating die ever made was made to role crimp. Taper crimp dies came into vogue when 10mm and 40 S&W with their high pressures became popular. If you had said you were loading either of those caliber’s then I would say you MIGHT need to use a taper crimp die but with 45, 9mm, 38 special, 357 mag and any of the old S&W or Colt caliber’s taper crimp dies are an unnecessary expense IMHO. It is however VERY IMPORTANT to have all your brass uniformed in length when using a role crimp and you must pay close attention to your die setup and be careful not to over crimp which can result in bad head-spacing and or failure to chamber from bulged cases.
HTH

[psteinmayer]

In an auto pistol the cartridge seldom headspaces on the shoulder of the chamber. As the cartridge feeds out of the magazine it slides up the face of the breechblock and under the extractor. The extractor holds it through the firing process. In Hatcher's Hatcher's Notebook he describes firing .380 ACP (9mm Kurz) in a 9mm Luger. The .380 cartridge slides up under the extractor and fires normally even with over 70 thousandths excessive headspace. Naturally the .380 cartridge wouldn't cycle the action of the Luger, but it safely fired.

That may be true of firing a luger... but a .45 does headspace on the case mouth. A .45 that doesn't properly headspace could result in a release of potentially hazardous gasses... just the same as a improperly headspaced 30-06. The best bet IMHO is to stay away from roll-crimps. Lee has a factory crimp die for .45 ACP which forms a proper crimp and resizes the case from expansion, creating a cartridge that should never jam or foul. It's the only crimp I use and I've never had a problem!

[da gimp]

9mmP headspaces on the case mouth too, just like a .45ACP.............. with proper expanding ball/rod & good dies, taper crimps are at best unnecessary & make it harder for the loaded round to headspace properly if at all.........

[Hefights]

Get a taper crimp die for .45 ACP or 9mm, it will do a better job. Taper crimp die facilitates proper headspace for those cartridges. If you can do it with a std seater die in the same step as bullet seating more power to you, but my experience is that the taper crimp die does a better job. Missouri mules tend to stick with what works for them, and I am one of them

[gatorbone]

I bought a taper crimping die and lo and behold things work sooooo much better. Feel a lot more comfortable now. performance is to be determined. Should be a lot better. Thanks to all for the wisdom and insight. Kim

[Hefights]

My experience was exactly the same, years ago. I am sure that one can "taper crimp" with a regular die somehow, at least of a sort, and that now modern Lee Dies (and perhaps others) are set up for that. Howver, all I remember is that trying to get a good quality crimp on a .45 ACP with a standard seater/crimper die in the same step was a real pain, with mediocre results. Perhaps I just didn't have the knack nor the patience.

But when I got the taper crimp die, and went to a separate step, and then got my Dillon 550, all became right with the world, smooth, easy with a very professional end product,

and for the others who disagree adamantly, well, Your Mileage May Indeed Vary, and is entitled to do so!

[duke133]

Johnny P. I just saw you mention of firing a 380 in a 9 and it brought back memories of my firearms instructor course years ago. They would load your mags for the combat course and slip a 380 in somewhere along the line, sometimes more than one, which would simulate a malfunction of your weapon during the course. The rounds always shot but never ejected and caused some to hesitate tooooo long, as in you're dead, try again!