How low can I go?

[Aguila Blanca]

It appears Zukiphile has found the holy grail -- a stock barrel available for an affordable price in .380 ACP. I wish they offered a Commander length, but that's nothing a hacksaw can't fix.

Browning 1911-380 magazines won't work. They are scaled down, just like the pistol itself. I'll have to use 9mm magazines and hope I don't have to tweak the feed lips.

[zukiphile]

Someone on one board wrote that he used 9mm magazines, but then on another board, someone else wrote that he had a feeding problem he attributed to the lips on 9mm mags not holding the round long enough...I think.

Yet another fellow wrote about using a makarov barrel as a sleeve in a 45acp barrel. If memory serves, he was the one who used a 7 pound spring.

A lot of this was over my head and I was procrastinating as much as researching.

[Unclenick]

The SAAMI maximum length of a 380 is 0.984" and the minimum for 9mm is 1.00". Those are close enough that I would expect full-length 380 FMJs to function in a 9mm magazine. If it proves to be a problem. For shorter hollow point loads, it may well be an issue.

I still wonder, since the angle of the reduced-size Browning mag will still be right, if one might possibly use a 3D printer to extend the bottom and fill in the back and sides of it. Be some trimming and fiddling work, but it might be possible to work out an adapter for one that the front toe has been trimmed off of. I've never seen one up close, so I am just speculating here.

The barrel Zukiphile found claims to be a match barrel, but I can't make out the usual dog nut you see on those. That's good because that means it can, indeed, be shortened and recrowned. But having someone with a lathe add the dog nut to match the shorter length will make it easier to fit a solid bushing closely if shooting precision is of interest.

[zukiphile]

Originally Posted by Unclenick

I still wonder, since the angle of the reduced-size Browning mag will still be right, if one might possibly use a 3D printer to extend the bottom and fill in the back and sides of it. Be some trimming and fiddling work, but it might be possible to work out an adapter for one that the front toe has been trimmed off of. I've never seen one up close, so I am just speculating here.

Just an spin on your speculation:

Old AR15 22lr conversion kits mounted a 22lr magazine inside a standard 20 round 5.56 magazine.

I wonder if a Browning 380 magazine could be mounted inside a standard magazine with spacers.

[Aguila Blanca]

My experiments trying to shoot .380 ACP through a .38 Super barrel were several years ago so my memory is less than crystal clear, but I'm certain I didn't make up any custom or hybrid magazines, so I must have used wither 9mm or .38 Super mags.

Now that I think about it, .38 Super cases are slightly smaller than 9mm, so perhaps the ticket will be .38 Super magazine bodies, a custom spacer, and 9mm followers and springs.

First step will be the barrel.

[74A95]

Originally Posted by Aguila Blanca

Now that I think about it, .38 Super cases are slightly smaller than 9mm,

Nope. The 9mm max case dimension is .394 at the rim. The max 38 Super case dimension is .406 at the rim.

[Aguila Blanca]

Originally Posted by 74A95

Nope. The 9mm max case dimension is .394 at the rim. The max 38 Super case dimension is .406 at the rim.

Oops. I forgot about the semi-rimmed case for the .38 Super. I was thinking of the case diameter. .380 case is .3739, .38 Super case is .384, and 9mm case tapers from .3910 to .3811.

So . . . trial and error.

[Jim Watson]

So buy a new barrel rather than just light load 9mm P where magazines would be no issue?

I have some light recoil springs and no early demand for additional standard 9mm ammo.
I will see what powder puffs I can flange up.

Reverse ladder loaded, watch this space.

[Jim Watson]

Powderpuff 9mm

Gun: Colt 1991A1 5" with 7 lb recoil spring, well oiled. I do not have a 9mm Commander.
Bullet: Xtreme 115 gr plated. I do not have any loose .380 bullets. Yes you can load 115 gr in .380 if you can keep the OAL down.
Powder: HP38 =W231
Primer: WW SP
Brass: Mixed

115 gr Xtreme plated

4.2 gr HP38 1040 fps f 119
3.9 gr HP38 999 fps f 114
3.7 gr HP38 914 fps f 105
3.5 gr HP38 880 fps f 100
3.3 gr HP38 702 fps f 89 Failure to Eject
3.1 gr HP38 674 fps f 77 Failure to Eject

3.5 gr was the least to get off three shots with ejection and slide lock. Comfortable to shoot in that heavy gun. The f number is power factor, recoil is proportional to that momentum value. Regular econoball or my IDPA ESP ammo is f 132.

Velocity variations in these extra light loads were high, some over 100 fps. If available I would use a fast flake powder instead of 231. Bullseye, N310, or Clays, maybe. Short OAL would probably help, too.


For comparison
.380 Colt Gov't Model 3.5" barrel
100 gr Xtreme
3.2 gr HP38 841 fps f 84

Snappy in that small gun, but if you could get a Commander that low, it would be very mild.

[ciwsguy]

Originally Posted by Aguila Blanca

I recently encountered someone who wants to learn to shoot, is recoil sensitive, and who doesn't want to learn on a .22 because it's "not enough for self defense."

I have a couple of pocket 380s, but even I recognize that they can be a bit "snappy," and the triggers aren't great. Being a 1911 guy, I have long dreamed of building a 1911 chambered in .380 ACP just for situations like this, but I haven't found anyone who can/will build me a .380 barrel for a 1911.

So the easy way out would be to download a batch of 9mm and use my 9mm Commander for instructing this person. I have Winchester 231 for powder. For projectiles, I have 9mm projectiles in 115 gr, 124 gr, and 147 gr. I also have some 95 gr bullets for reloading .380 (which I have only done once).

What's the better way to get a reduced recoil 9mm load: use the 95 gr projectiles, or use the 115 gr? If I want to replicate the ballistics (recoil) of a light .380, how can I determine what to use as a powder charge?

There are some low-recoil semi auto pistols on the market, S&W 380 EZ is one, and Walther makes some gas operated semi auto pistols that take away some of the recoil. My guess is that this person also doesn't like a "heavy" handgun (i.e., a steel revolver) because it's too heavy to hold. They might want to look at getting a stun gun.