380 acp from .233 Rem?

You could make 380 ACP cases from 223 Remcases but you would have to thin the case mouth to make room for the bullet.

Without thinning the brass at the case mouth, the cartridge will not chamber, at best, or get stuck in the chamber, at worst. The latter is very undesireable.

Check the SAAMI drawings and spec's. The internal dimensions of the bases are off, too. You'd have to take out a lot of brass from the base of a .223Rem to make the volume match a .380ACP. That's assuming you really are looking at .223Rem and not 5.56mm NATO, which is even thicker at the base.

joneb said:

Maybe? Or why not reduce the amount of powder? and just ream out for the bullet.
The inside diameter of a sized 380acp case is about .351-.352" the tricky part would be the reaming. My thought is making a reamer/cutter from a .35 cal Lyman case trimmer pilot.
I doubt I will never need to pursue such a thing, but ya never know The same could be possible for 45acp from .308 Win. ???

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I would think if you had a lathe it’s doable.
That said, it seem not very practical. But if one was looking for a project I guess I would be as good as any.

Wow, are 380 cases really that hard to come by in other regions of the country? Sure, it could be done, but I can't see it would be worth the time.

From my copy of The Handloader's Manual of Cartridge Conversions:

"CASE PREPARATION:
MAKE FROM: .222 or .223 Rem. cut case off to .68" long. Inside neck ream for .355 projectile. F/L size. Not really worth the effort - commercial cases are easy to find."

^^^ It's always nice to have options.

I actually just got my copy of The Handloader's Manual of Cartridge Conversions, after someone mentioned it in another thread here. It's definitely a great reference to have in my reloading library.

joneb said:

Not yet, but the way things are going.... who knows.

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You wouldn't know there's an ammo shortage at the range I shoot at. I usually come home with at least a half of a 5 gal bucket of brass each weekend. I have enough brass for my lifetime.

GravelRider said:

^^^ It's always nice to have options.

I actually just got my copy of The Handloader's Manual of Cartridge Conversions, after someone mentioned it in another thread here. It's definitely a great reference to have in my reloading library.

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I use it but take it as a set of helpful suggestions of what to look for, not the final word. Example being 9mm Makarov. The conversion is a lot less complex than the guide suggests.

dartor said:

You wouldn't know there's an ammo shortage at the range I shoot at. I usually come home with at least a half of a 5 gal bucket of brass each weekend. I have enough brass for my lifetime.

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At my favorite range there’s seldom ANY brass of any kind in the cans. I’m surprised there’s not someone there catching brass as it’s ejected. Even have some guys that come out just to dig lead out of the backstops.
Even so, making 380 out of 223 would be very far down on my list of priorities.

I attempted this once upon a time. It proved to be a total waist of time. Would be less work to swage & trim a 9x19.

joneb said:

I have trimmed down Winchester 9x19 to make 9x18 Mak brass it works very well. I chose Win. brass as it was one of the lightest 9x19 cases I had, and I have a lot of it.

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Oh, it works alright. I’d done it before, years ago. Just couldn’t quite remember how. That’s what happens when you start to get old. I had to refresh my recollection because what the guide says was a lot more steps than I thought ought to be. It’s a good guide, don’t get me wrong, but the authors kinda assume you have access to a full machine shop. If you don’t... well, it can be a little frustrating.

Bcwitt said:

I attempted this once upon a time. It proved to be a total waist of time. Would be less work to swage & trim a 9x19.

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Do you remember exactly what went wrong? Might be helpful to the OP. And I’m just a little curious.

GeoDudeFlorida said:

Do you remember exactly what went wrong? Might be helpful to the OP. And I’m just a little curious.

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I attempted to ream out the case w a drill press. Ended up w crooked case that was too thin towards one side. You might be able to make a reamer or a cutter to do that, but drill bits would always drift. Perhaps a lathe would work, but till you count your time, you end up w cases costing more then the gun.

Does anyone recall the old Grendel P10 380 ACP automatic? Here's a random article, selected for the picture: https://laststandonzombieisland.com...ere-was-kel-tec-the-evolutionary-grendel-p10/

It had an integral magazine, and was meant to be able to be loaded by stripper clip. (You didn't have to; but you could if you had clipped up 380 ammo.) The stripper clip you were meant to use was actually for 223 ammunition. I am so ignorant about AR-15 / M-16 rifles that I do not know if the stripper clip was for them, somehow. Anyway, you can see it in the picture in the link.

And that is everything I have ever known about the similarity between 380 ACP and 223. Sorry if it's a meaningless digression in this thread, but it fired off a memory.

Bcwitt said:

I attempted to ream out the case w a drill press. Ended up w crooked case that was too thin towards one side. You might be able to make a reamer or a cutter to do that, but drill bits would always drift. Perhaps a lathe would work, but till you count your time, you end up w cases costing more then the gun.

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Yup, and there’s the first thing that gets a little frustrating: cartridge bases aren’t trued. Trying to true them up THEN inside bore is a tedious, time consuming process. I kinda like the idea of using a trimming tool sized for the job - but now you’re talking grinder work.

joneb said:

Trimming 9x19 Luger brass to 9x18 Makarov brass just requires a case trimmer, pretty easy just takes a bit of time.
Getting on to original topic regarding reaming the inside of the case mouth of the cut down 223 Rem case to load 380acp could get a bit fiddly.

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Now, don't get me wrong. I'm not saying it can't be done, or even that it shouldn't be done. All I'm saying is, there's maybe a lot more to it than just cutting the front half off a rifle case to make a pistol case. I'd hate to see somebody eat a slide because they forgot to compensate for a change in volume. That's all.

I would just give up the 380 before I would even consider doing this. I am not that fond of the cartridge anyway. I like to make things, fix things, tinker with things, but this one is completely outside my interest range. To those of you that want to give this a try---good luck and be careful, very careful.

doubleh said:

I would just give up the 380 before I would even consider doing this. I am not that fond of the cartridge anyway. I like to make things, fix things, tinker with things, but this one is completely outside my interest range. To those of you that want to give this a try---good luck and be careful, very careful.

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I understand and I think a lot of folks probably agree but you have to admit, it's an interesting and useful set of skills to acquire Thing is, once you have those skills, if you don't use them you lose them.