9mm bullets for 380ACP

[FieroCDSP]

I'm going to be doing some load work-ups for a 380Auto and was wondering what results (or warnings) others have had with using a 9mm bullet (specificly a 115gr encapsulated) in the 380. The diameter is the same, but 9mm bullets usually have the longer length.

If it feeds, use it? Or should I forget it? I have 380 bullets, but I also have a bunch of 9mm floating around and was curious if anyone has tried it.

 

[lee n. field]

115 might be a bit heavy (you know it is).

 

[Jim Watson]

I have seen data, and used it to load 115 gr .380s. Lyman maybe.

 

[Walkalong]

I'ts not worth the trouble, although you can make it work.

 

[Wil Terry]

Encapsulated Bullets.....?????

I want some too.

 

[TN Shooter]

The biggest potential issue is the OAL of the .380 cartridge with a 115 gr. bullet. The ogive on a .380 bullet is much shorter than on a 9mm bullet, so if you if you seated the 115 gr. bullet deep enough to obtain the correct OAL then there is a chance that the case mouth would be unsupported.

 

[FieroCDSP]

Wil, it's a plain TMJ, AKA encapsulated.

 

[rcmodel]

You may also run into case bulging in some brands of cases.

The longer bullet has to be seated deeper to keep OAL correct, and the base of the bullet may be deep enough to get into the thicker case web and cause it to bulge out when the bullet is seated.


rcmodel

 

[CZ57]

It will depend on the pistol and it's ability to feed a round that will be near the OACL maximum of .984".

In the Lyman 46th, they loaded the 115 gr. Hornady to .956. 3.4 grs. of Unique achieved 973 FPS @ 15,900 CUP. With 4.5 grains of HS-6, they obtained 945 FPS @ 15,200 CUP. Velosities were recorded with a 3.75" test barrel. These loads are Max. At that time the presure max for .380 ACP was 18,900 CUP. There are several powders that you can use, I just listed the two that gave the best performance and because SPEER got the best performance with HS-6.

SPEER loaded it a little warmer in the #11 and achieved the highest velocity with 5.3 grains of HS-6. Velocity was 997 FPS recorded in a Browning pistol with a 4.5" barrel. Don't ask me which one (SPEER didn't specify) beacuse I can't remember a Browning .380 with a 4.5" barrel. Speer loaded Unique to 4.0 grs. for 968 FPS.

If it were me, I'd use a 115 gr. JHP that will be shorter than an FMJ.

 

[FieroCDSP]

If it were me, I'd use a 115 gr. JHP that will be shorter than an FMJ

CZ, thanks. I was looking at the 115XTP load in the Lyman 48th, and might go with that for a defensive practice load, and just from looking at the lengths, I think I'm going to keep these round nose 115's for my 9mm.

Thanks everyone for their responses.

 

[CZ57]

Fiero, I should have mentioned that the 115 gr. Hornady that Lyman used was the JHP that preceded the XTP. Data is typically identical. Remington 115s in bulk are a very good deal. Great bullet. I use it on occasion in 9mm, but mostly their 124 gr. JHP. About the lightest constructed conventional 115 that I know of is the Winchester 115 JHP that you can also buy in bulk. This is one case where the 115 gr. Silvertip might be a good choice because of the lower velocity. The Silvertip is even lighter constructed than the standard 115 because of the Silvertips aluminum alloy jacket.

 

[FM12]

I load 115 FMJ and JHP Zero for my government .380, using 2.5 grains of Bullseye. i did this when I ran out of light weight .355 bullets designed for the .380. Proper bullet size for the .380 is, by the way, .355. Seat the bullet to where it will reliably function thru the magazine.

DON'T go overboard on the powder. No gains there.

 

[Clark]

CAUTION: The following post includes loading data beyond currently published maximums for this cartridge. USE AT YOUR OWN RISK. Neither the writer, The High Road, nor the staff of THR assume any liability for any damage or injury resulting from use of this information.

I load for 3 different levels of .380:

1) Kel-Tec P3AT 6 ounces empty 10 ounces loaded, it has a locked breech, poor case support, and thin chamber walls. The steel and heat treat used is good, but it is the only pistol with a thinner chamber than the CZ52, but the steel is RC47, and the CZ52 is as low as RC26, so the steel in the P3AT is nearly twice as strong.
Designed and built in 2003
With the 110 gr JHP, I use 5 gr Power pistol or 6.5 gr 800X.
With the 90 gr Gold Dot I use 6 gr Power Pistol or 7.2 gr 800X

2) Beretta 1934 22 ounces empty, blow back, ok case support, thick chamber walls.
designed in 1934, built in 1943.
90 gr XTP 7.6 gr Power Pistol, pistol needs more recoil spring to go higher.


3) Colt 1903 33 ounces empty, blow back, thick chamber walls, good case support.
Designed in 1903, built in ~1910
158 gr XTP, 8.5 gr Power Pistol, 1187 fps

What does it all mean?
1) Some 380s can exceed 357 mag, while others cannot reach 9mm Luger performance.
2) Modern materials and modern design are not as important as case support, thick steel, and heavy mass.