Can I use a roll crimp for .32 ACP?

[Mr. Farknocker]

I'm getting ready to reload some .32 ACP rounds for the first time and have a question about crimping. My Lee Precision Die set comes with a bullet seater and, with what I understand, a roll crimp. I understand that roll crimps are recommended for revolvers while tapered crimps are recommended for auto rounds. Since I'm reloading the .32s for my semi-auto pistol, my thinking is that I need to use a tapered crimp instead of a roll crimp. Problem is Lee doesn't sell a Factory Crimp (aka tapered crimp) die for my .32 ACP. Should I be concerned about using a roll crimp on my lead cast bullets for my hand gun instead of a tapered crimp? BTW, the lead cast bullets that I have appear to have a crimp groove.

[waco]

I would not use a roll crimp because the cartridge headspaces off the mouth of the case. You should tapper crimp.

[dougader]

32 auto is a semi-rimmed case. Can you check your barrel and see for sure how the ammo headspaces to be sure?

When I first started loading 9mm my old RCBS dies came with a roll crimp, too. I bought a Dillon taper crimp die some years later, but up until then I just applied enough crimp to remove the bell in the case and it worked fine. Of course, case length played a much bigger role when I was using the roll crimp die.

[ku4hx]

... a Factory Crimp (aka tapered crimp) ...

The two are not necessarily the same. A taper crimp die is just that, a very slightly tapered highly polished tube (in the form of a die) that removes case flare and [gently] presses the case neck against the boolit to achieve desired neck diameter without rolling the case lip. A Lee "factory crimp" die is a gismo within a die that at the very last operation, squeezes the upper most part of the case mouth around the boolit I'm not aware of every single crimp die Lee makes, but the "FCDs" I have work fine for bottle neck cases but for cases that headspace on the case mouth, a true taper crimp is far better, in my estimation it's essential, for proper case neck diameter.

All my dies of all makes bought when I first started loading circa 1970 had roll crimp seating dies. That included 9mm and 45 ACP. You could get a proper "taper" crimp with them, but if you weren't very careful in setting the die, you could roll crimp the case and deform the boolit. I did that a number of times then finally wised up and bought true taper crimp dies.

[texassako]

I use the Lee .32 ACP die set, and never get to the actual crimp portion of the seating die when seating cast boolits. I just go far enough in to remove the case flare and slightly push the mouth into the side of the boolit to prevent boolit setback when feeding. My first loads went all the way to crimp and swaged the boolit down to jacketed size.

[Mk42gunner]

Yes you can roll crimp the rounds for an auto, just don't go overboard with it. Lyman sells a taper crimp die for the .32 ACP if you really need one, but you should be able to load perfectly serviceable ammo with the set you have.

Reread texassako's post, he describes how to do it more eloquently than I can.

Robert

[Shiloh]

I'd not recommend it. Try a enough to just close the bell and no more.

Shiloh

[Wheeljack]

In my case a 9mm. The lee Factory Crimp, without using the Crimp Adjuster gives me a .378 neck. The shell is .012 thick, so the bullet is squeezed from its cast .357 to .354. Is this .003 squeeze enough or should I use the Crimp Adjuster to give it a little more and how much more? The added crimp from the Crimp Adjuster does not seem to be a roll crimp at all but a taper crimp.

[Outpost75]

75874

The .32 ACP is semi-rimmed, like the .38 Super and normally headspaces on the semi-rim. Sloppy fit of rounds in the chamber and variation in cartridge orientation thereby does affect accuracy. That is why the .38 Super was never popular until Irv Stone and Bob Chow started making match barrels in the 1960s, which headspaced on the case mouth and removed the excess "slop" in the chambers.

If you make a new .32 ACP barrel, however, rather than use a standard .32 ACP reamer instead use the front of a .30 M1 Carbine chamber reamer, running it in short, and setting up the barrel to headspace on the case mouth, like a true rimmless cartridge, using European CIP specification factory rounds as a gage.

Accuracy is very much improved for the .32 ACP, every bit as much as it was for .38 Super "race guns" with good barrels set up to headspace on the case mouth.

The difference is dramatic! The .32 ACP cartridge is inherently accurate if you give it a chance. My "squirrel gun" uses a standard .30 caliber ten-inch twist barrel. X-ring 25-yard groups are possible with a target-grade match pistol with scope. In a more compact 4"-5" barrel, iron-sighted field gun they will shoot better than you can hold.

75873
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[10mmShooter]

I shoot a 1910 Mauser in 6.35mm Browning, taper crimp is what I use, the little Mauser is very sensitive to cartridge length. I have to deep seat my 78 gr RCBS LRN bullets to .910 COAL otherwise the slide wont go into battery. Little gun functions flawlessly with 1.5 grains of WW231, not too bad for a 100 year gun. It was bought home by my Great Aunt after WWII.

[wallenba]

Confused about how much taper crimp is enough? I was, maybe I still am a bit. What I do is measure the case wall thickness, multiply be two. Add that to the boolit diameter for the overall outside diameter of the loaded round. Then slowly adjust the TC die until it is about .001 less than that diameter. It may cause the boolit to be resized to a smaller diameter than you want for your groove, so choose a larger sizing die to start with if you have too. That should hold it tight enough.

[gray wolf]

32 auto is a semi-rimmed case. Can you check your barrel and see for sure how the ammo head spaces to be sure?


It all depends on the pistol, You have to check the chamber.
With a semi rimmed case it could very well head space off the rim and many do.
If the forward movement of the case is stopped by the case rim then that's it, it ain't going any deeper, use a light roll crimp into the bullet crimp groove.
Julies Beretta tom cat is such a pistol and I use a slight roll crimp.
She shoots the RCBS 77 grain bullet. Just fold the case mouth in a little, if they cycle and chamber OK you should be fine. What pistol are you shooting ?
Got a Pic of the chamber end of the barrel ?