Home
Posted By: northcountry 9MM in 38/357Mag. - 10/10/19
I have a question for the experienced hand gunners on here. If you load 9MM bullets in a 38/357Mag how much velocity will you loss because of the smaller 9MM bullet about 2 thousands I believe. Thanks for your time. Cheers NC
Posted By: The_Real_Hawkeye Re: 9MM in 38/357Mag. - 10/10/19
Link to discussion.
Posted By: okie john Re: 9MM in 38/357Mag. - 10/10/19
I'd be more concerned about losing accuracy, but bore diameter is only part of the equation. Bullet pull will be less since the case isn't sized enough to hold the bullet tightly, which can cause erratic ignition and that's where things really go south. That said, you might be able to get away with this using jacketed bullets but it's definitely a bad idea with cast bullets, which should be about .002" OVER bore diameter for best results. Undersized cast bullets lead like crazy and are wildly inaccurate, so they're basically a waste of powder and primers.


Okie John
Posted By: The_Real_Hawkeye Re: 9MM in 38/357Mag. - 10/10/19
Posted By: antelope_sniper Re: 9MM in 38/357Mag. - 10/10/19
Originally Posted by okie john
I'd be more concerned about losing accuracy, but bore diameter is only part of the equation. Bullet pull will be less since the case isn't sized enough to hold the bullet tightly, which can cause erratic ignition and that's where things really go south. That said, you might be able to get away with this using jacketed bullets but it's definitely a bad idea with cast bullets, which should be about .002" OVER bore diameter for best results. Undersized cast bullets lead like crazy and are wildly inaccurate, so they're basically a waste of powder and primers.


Okie John


This.

I had a .38 super, bore on those is an odd diameter, .356. I only shot it with jacketed bullets. It shot very well with .357 bullets, but .355 bullets didn't shot well at all.
Posted By: Jim in Idaho Re: 9MM in 38/357Mag. - 10/10/19
Back in the 80's a fellow gave me a water damaged box of 500 Speer swaged lead 124 RN bullets for 9mm. Having no 9mm pistol I loaded them in .38 Special cases to use in my S&W 586. I forget the powder charge but back then it was most likely some middlin' level of 231.

Did not have a chronograph to measure velocity but being such soft lead with a fast burning powder they obturated well and were definitely minute of soda can out to 25-30 yards with no leading or other issues. Hard cast bullets probably would not have fared so well but I can't say for certain since that was my only experience with this.
Posted By: T_O_M Re: 9MM in 38/357Mag. - 10/10/19
Originally Posted by northcountry
I have a question for the experienced hand gunners on here. If you load 9MM bullets in a 38/357Mag how much velocity will you loss because of the smaller 9MM bullet about 2 thousands I believe. Thanks for your time. Cheers NC


Not enough to worry about. Maybe some leading with cast / swaged bullets.

I sometimes load .380 ACP bullets ... .355, 88 and 90 grains ... in .357 mag cases or .357 maxi cases, taper-crimped, for shooting jackrabbits. I don't recall what my .357 mag load was. They were for a Ruger 77/357 bolt action so I didn't have to worry about magazine spring tension, etc. The .357 maxi loads used 31 grains of either H110 or Win 296. Don't know that I'd use them in a revolver, might have some problems with the forcing cone, but in a solid barrel like the bolt action or Contender they worked well for me.

Tom
Posted By: Dillonbuck Re: 9MM in 38/357Mag. - 10/10/19
As others have said,
Be sure you have enough neck tension.

Lead would probably be best.
If the bullets are soft enough, or the load is brisk enough,
You will get enough obturation to seal and spin.
Or, you could overdrive the alloy.


I would certainly try.


Also, faster powders might be better.

Unique is my stand by, the only thing I have used much of
in its class. It has a reputation for hitting bullets hard enough to
bump them up. Haven't used other powders, so I can't compare.
Posted By: ratsmacker Re: 9MM in 38/357Mag. - 10/10/19
Originally Posted by Jim in Idaho
Back in the 80's a fellow gave me a water damaged box of 500 Speer swaged lead 124 RN bullets for 9mm. Having no 9mm pistol I loaded them in .38 Special cases to use in my S&W 586. I forget the powder charge but back then it was most likely some middlin' level of 231.

Did not have a chronograph to measure velocity but being such soft lead with a fast burning powder they obturated well and were definitely minute of soda can out to 25-30 yards with no leading or other issues. Hard cast bullets probably would not have fared so well but I can't say for certain since that was my only experience with this.




Those were/are good bullets, I used a lot of them when I got my first 9mm (Smith 39-2). We had an RCBS/Speer jobber just off-post, and I'd ride down there and buy a box or two of them and the 452 LRN .45 bullets, and load them up for my pistols. I was using 231 as my only powder then, too. I got a lot out of the milder loads, they taught me how important trigger control and sight picture were. I was a pretty good pistol shot by the time I got out of the Army, and none of it was due to the Army,
Posted By: northcountry Re: 9MM in 38/357Mag. - 10/10/19
Thanks for all the replies it is appreciated and looks like it might be a decent option for practice. Cheers NC
© 24hourcampfire