Loading 9mm with 357 bullets.

Model5

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Good afternoon. I’ve looked around some online and in this forum but haven’t come up with a whole lot of answers as far as real world experiences. So basically I had a wild idea yesterday at work. I have an abundance of 357 bullets of different varieties. I was curious if I could size down from 357 to 355. So as per my usual having some free time I made a sizing die with a pusher. I am able to size the bullets down to .3555, now my first question is. Will that be acceptable or do I need to size down further to .355+0.0/-x amount or will .00025” a side be a non issue? I did pull apart a few different 9mm cartridges to gather information and they bullets from those varied from .3544” to .355”. To get around the whole $150 dies that I refuse to pay that much for I plan on makeing my own. What has been your experience if you went down this rabbit hole?
 

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The shape of the bullet may keep the .357 bullet from seating in a 9mm chamber. This is my concern seeing your bullet pic.
Feeding into the chamber is also suspect. That ctg looks kinda long. What bullet weight is that?
Be careful.
Jim
 
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It's a non-issue with normal published 9mm loads in a modern quality pistol. I've used .356 in 9mm.
Now if you're wanting +P+ through your vintage Luger, you're asking for trouble already, not to mention oversize bullets. Watch you length, and plunk test.
 
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Jacketed bullets, like yours, are going for a premium around here on the local gun trader. I would be tempted to sell your jacketed bullets, even in odd quantities, and then use the proceeds to get some properly-sized, and weight, bullets from say Xtreme. I just checked their website, this morning, and they had a lot of .40 sized bullets in stock ... I didn’t check 9mm but I bet they have them too.
 
The shape of the bullet may keep the .357 bullet from seating in a 9mm chamber. This is my concern seeing your bullet pic.
Feeding into the chamber is also suspect. That ctg looks kinda long. What bullet weight is that?
Be careful.
Jim

The bullet is 125gr jhp. That’s part of the reason I pulled the other rounds to check diameter and have sized cases to test feeding from a magazine. It will cycle by hand and not hang up with the slide being dropped on it. The bearing surface is very distinct after resizing and measures about the same length as the 115gr fmj I pulled.
 
Pretty much any 110gr or 125gr resized down to .355 should be fine in pretty much any 9mm. Those weight shouldn't be too long or seat too deep. Heavier weights would more likely be too long and have to seat too deeply in the case.
I'd be the most comfortable with using hard cast lead for this kind of resizing experiment. Lead will resize better and create less pressure than jacketed, which may spring back a little and end up being a bit bigger.
 
Pretty much any 110gr or 125gr resized down to .355 should be fine in pretty much any 9mm. Those weight shouldn't be too long or seat too deep. Heavier weights would more likely be too long and have to seat too deeply in the case.
I'd be the most comfortable with using hard cast lead for this kind of resizing experiment. Lead will resize better and create less pressure than jacketed, which may spring back a little and end up being a bit bigger.

I’m just trying to avoid purchasing any more bullets since I have so many. And also the Glock manual specifically states not to use lead bullets due to the polygonal rifling causing pressure issues.
 
I loaded some 150gr .357 diameter SWC I had leftover from a failed endeavor involving a revolver. They actually fed and shot very well in the only gun I tried them in, a Springfield 1911. I did use U.S. brass. But one could run into chambering issues. I intend to retry that in the near future.
 
I loaded some 150gr .357 diameter SWC I had leftover from a failed endeavor involving a revolver. They actually fed and shot very well in the only gun I tried them in, a Springfield 1911. I did use U.S. brass. But one could run into chambering issues. I intend to retry that in the near future.

The sizer I made does a consistent.3555”. The dummy round I made plunks good and it will chamber from a mag with the slide dropped from the locked position.
 
The sizer I made does a consistent.3555”. The dummy round I made plunks good and it will chamber from a mag with the slide dropped from the locked position.

I think that should be fine. Just proceed with the same caution you would developing any other load.
 
The sizer I made does a consistent.3555”. The dummy round I made plunks good and it will chamber from a mag with the slide dropped from the locked position.

If it plunks, fits the mag and feeds, and you're a cautious and experienced handloader, it's worth pursuing.
 
This thread made me a little curious, so I decided I’d give it a try too. I have some .38/.357 Rem Golden Saber 125gr. that I thought should work. I ran one through a .355 sizing die and loaded a dummy round to 1.125” OAL. It looks a little funny, but plunked just fine in a P239 9mm chamber. I’ve got a whole bunch of .38/.357 110 gr. Hornady XTPs I think I’m going to try out next.
 

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This thread made me a little curious, so I decided I’d give it a try too. I have some .38/.357 Rem Golden Saber 125gr. that I thought should work. I ran one through a .355 sizing die and loaded a dummy round to 1.125” OAL. It looks a little funny, but plunked just fine in a P239 9mm chamber. I’ve got a whole bunch of .38/.357 110 gr. Hornady XTPs I think I’m going to try out next.

Those look Juliet like my 124 golden sabers I carry.
 

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Re: loading 110 gr .357 dia XTPs in 9mm

Well, it might work. It makes a good looking round, I’ll say that. To get it to the top of the cannelure, I had to seat it to an OAL of 1.011”. It’s a much shorter bullet, so even at that OAL it has only .04” less case volume. If I bring it out to 1.05” OAL, case volume would be the same as with the Golden Saber and pressure shouldn’t be an issue. It might be fun to work up a load for. Just perusing some reloading manuals and doing some extrapolation, I think you could push it to around 1250 fps safely, starting low and working up. I’ve only been reloading a little over three years and have always stuck to proven recipes in manuals published by the big reloading houses, so I’d like to hear some thoughts about the possibilities of this from some more experienced reloaders.
 

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tlawler, that’s about the same approach as I’m taking. I’m not very worried about the cannelure since it’s not a full power 357 magnum. I’m more interested in maintaining a case capacity that will reproduce something along the lines of a published load so I know the data should be safe and accurate somewhat. I believe with loading for 38/357 now going off on a tangent with modifying bullets I need to purchase a chrono.
 
Years ago I routinely loaded 125-grain .357 JHP bullets in 9mm cases for my Browning Hi Power. No problems at all in that pistol.

I have also loaded cast lead SWC bullets designed for .38/.357 and sized to .357" in 9mm cases. Those also worked fine in my Browning.

Trying the same things later on with a Colt Government Model 9mm and a S&W 469 I found that neither one worked so well with those pistols. The issue with both appeared to be chamber dimensions that would not accept rounds loaded with the .357" bullets easily.

Since you are resizing to an appropriate diameter I think your plan should work pretty well. The only other major hurdle would be a bullet profile that functions with your pistol's feed ramp.
 
I’m just trying to avoid purchasing any more bullets since I have so many. And also the Glock manual specifically states not to use lead bullets due to the polygonal rifling causing pressure issues.
AH, you're loading for a Glock. Either you didn't say that earlier or I missed it. I know they don't like lead.

From your subsequent posts it looks like it is working out for you.
Just curious, how hard are those JHPs to push through the sizer?
 
Using 38/357 bullets in a 9mm pistol all depends on the chamber spec's.

My 3.5" barrel C9 9mm pistol would swallow .356" coated bullets.
the .357" bullets would bulge my mixed brass, but still chamber.

A coated .358" Dia. in the case was just too large in dia. to chamber or let the slide close.

It might work in your pistol, you just need to test you loads out.

Good loading.
 
AH, you're loading for a Glock. Either you didn't say that earlier or I missed it. I know they don't like lead.

From your subsequent posts it looks like it is working out for you.
Just curious, how hard are those JHPs to push through the sizer?

They aren’t too bad. Granted. I am lubing them with the lee case lube that came with my hand press from a couple years back. And pushing them through on my little arbor press.
 
If you are using a taper crimp die or a FCD you will probably find that your crimping stage is sizing the bullets down enough to properly chamber. The only advantage sizing the bullets first gives is that you can use the standard 9x19 expander plug. I do most of my loading on an old Dillon 450 and for me it's just a slight adjustment of the expansion plug to load 357 bullets in 9x19 cases. At least this has been my experience, your mileage may vary.
 
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