9mm Bullet for .357 Magum

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bkhann

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I brought in 100 ea 9mm coated lead bullets for evaluation that have a diameter of .357" (instead of .355/.356). These did not load well for 9mm (loaded case was too wide) so I will not use them for my 9mm loads.

Is there any reason that I should not use these for .357 loads? the diameter should be OK at .357 and a 125 grain RN bullet should not differ between 9mm and 357.
 
If they have a crimp groove, I'd load them in .357. If no crimp groove, you can probably still give them a try but load them light and check them for any bullet creep that might bind your cylinder.
 
They'll chamber ok in a .357, but accuracy will be problematic unless velocities are kept low....like .38 special target loads. Fast powder can "bump up" an undersized slug to some extent, but ".357" dia. is pretty small unless you have undersized cylinder throats and bore in your .357. Rod
 
Here's what I think about the situation... and this is really just me and I don't expect it to work for everyone.

If we were talking about 500 bullets or 3,000 bullets, I'd be looking for a shooting solution. For 100 bullets, I would give them away or tuck them on a back shelf to be tinkered with years down the road.

With that said, I think you can "safely" load them in .38 Special but your results may vary wildly on the revolver you shoot them in. What I think is likely to happen is that being undersized, they won't be very accurate. But more to the point -- being undersized may cause them to lead-up your barrel, coated or not.

If they lead up your barrel, you absolutely must be aware of it and ensure you get that lead out afterward. Lead in the barrel makes it incrementally SMALLER in diameter... when all else is equal, that translates to increased pressure across the board going forward until the lead is out.

I also believe if they lead up a barrel, the leading would be far worse at .357 Mag velocities (1200+) than at .38 Spl velocities (800-900fps.)

As side issue you may find quickly, long before you even shoot them. Depending on what brass you are using and the exact dimensions of your sizing die and how much flare you impart... you may find out right away that you simply won't get terrific bullet pull/case mouth tension on those slugs in .38 brass. If someone reads this and thinks "bah, never seen it" then I challenge you to find some 9mm slugs and load them in to R-P headstamp nickel .38 Special brass and report back. You may find something new you hadn't yet seen. ;)

For 100 bullets? I wouldn't goof with 'em simply because I typically have a goal in mind where the end game is "I have a lot of these, what is the best way to use them?" Thus, for me, trying to do my best with the wrong components is basically a waste of time for just 100 slugs.

Hope that helps.
 
No reason not to try them in your .357. By all means. However, I would keep the load lighter than a full-house magnum load, at least until you know that they will work.

So, do a test run loaded like .38 Special. If no problems, then step up the load, a bit at a time (normal procedure for working up ANY load).

Whether .357" diameter will be a problem in your particular revolver is an issue for either slugging the barrel......or shooting some test loads. If it were me, I'd do some test loads........
 
There is no reason they won't work in a 9mm. I suspect a loading error, not bullet diameter. I shot countless thousands .357 dia bullets out of a 38Super and a 9x21 with no problems at all. It's probably the crimp.
 
>I brought in 100 ea 9mm coated lead bullets for evaluation that have a diameter of .357" (instead of .355/.356). These did not load well for 9mm (loaded case was too wide) so I will not use them for my 9mm loads.

I hate to say it, but I bet there was something wrong with your loading technique. I load 0.358" lead bullets in all my 9x19s, including a tight chambered 1911 and CZ-75. This ranges from pre WWII P-08 "Lugers" to a new CZ-85.
I have not found a case with a wall so thick as to interfere with chambering these bullets (but I have seen bulges in cases from improper loading techniques that have prevented chambering).
Of course, if the weight and diameter are correct, they'll work for your .38 or .357, but they might cause some leading being that small.
 
Bkhann,

If the problem in 9mm was a feed problem, the cases you have may be thick enough at the neck that the extra 0.001" over standard cast bullet size may be making the fit a little snug. They can be sized down on your loading press using a Lee sizing die, and that may solve the problem.
 
What did that cost, $15? $18?

I'd stick my remaining bullets back in the box with a note about why they didn't work and move on. This stuff is cheap. You probably paid less for them than taking your wife out to breakfast. If your time doesn't matter and you really like tinkering, you've been well advised, but I would have a h are time caring. About those bullets.
 
I think that I will put the .357 9mm bullet project on the back burner. I suspect that the problem might be reloading technique issue. 100 bullets is just not a terribly big deal.

The original thought was to run these through my CZ 75 to see in there was a noticeable difference in accuracy. I did not plunk test the set up bullets that I loaded (no powder, no primer, just case and bullet). These are the examples that did not pass my case gauge.

Maybe in a week or so I will try loading some more set up rounds.

Thank you all for your feedback,

BobH
 
briandg said:
What did that cost, $15? $18?
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You generally purchase reloading equipment on the premise you will have additional use for it. If you know you won't, then, no, it's not worth the cost.
 
I also buy bread, avocados, and steak on the premise that I'm going to use them, but sometimes my avocados aren't so great and rather than pick through the nasty bits, I'll just put that box of bullets back on the shelf and maybe fart around with it later. I've got dozens of things on the shelves that just didn't work out. Maybe I should stubbornly keep plugging, but I try to avoid that sort of frustration.
 
Am I the only one that's shot .357 diameter cast bullets in my .357mag without a problem?
One of my preferred loads was 5 grains of 700-x(.1g over max on the Hodgdon's website) without any leading issues at all from a hardcast 158g semi-wadcutter. I put about 300 rounds down range without a single problem.
 
If the cast bullets are soft enough, a charge of fast powder can upset them enough to fill the bore. But if the bullets are hard and the bore is much over nominal groove diameter, or if your chamber throats are smaller than your bore groove diameter, or if you have a bad constriction of the bore where it screws into the revolver frame due to overly tight threads, you may never get lead to shoot well until corrective measures are taken. All those problems are surprisingly common, which is why you hear a good deal of grumbling. If your gun shoots well with no leading, say "thank you" to the manufacturer for that one.

SAAMI 357 groove diameter standard with tolerance range: 0.355-0.359"
SAAMI 357 chamber throat standard with tolerance range: 0.358-0.362"

Back when revolvers were more commonly used in bull's eye matches, the first step the target shooter's revolver smiths used to take was to ream all the cylinder throats to maximum or at least a thousandth over maximum groove diameter and make them uniform. You can firelap or hand lap a constriction out of the breech end of the barrel. You can cast and size your bullets from about half a thousandth under to right at your chamber throat diameters, and, assuming your chamber throats are all the same (again, commonly not the case out of the box, but corrected by reaming to maximum), and are at least half a thousandth over your groove diameter, this usually shoots very well.

From the SAAMI throat dimension standard, you can see the minimum throat is why commercial lead bullets are 0.358" standard, even though cast bullets 0.002" over groove diameter often shoots better in revolvers. 0.359" would jam in some throats.
 
Am I the only one that's shot .357 diameter cast bullets in my .357mag without a problem?
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No, and it cracks me up to hear everybody just assume that .001" is going to cause massive leading and poor accuracy.

1. You bullet changes diameter as soon as the charge is ignited. Pressure and bullet construction determine how much.

2. About half the 9mm guns out there with that supposed .355" bore have as big or bigger bores than half the 357's out there.


I can guarantee that your evaluation AFTER testing will be a lot more useable in your reloading life, than the internet evaluation before testing. Load some up, and tell us how it turns out.
 
Every bullet I've fired in my .357 Magnum (and a lot of my 38s) is .357"-.358" cast or jacketed. I would not hesitate to fire a plated bullet, using cast data, of .357" diameter in any of my revolvers. If I had a lot of them, I'd get a taper crimp die, or if just a few, I'd use my Redding Profile Crimp die to lightly crimp...

I can guarantee that your evaluation AFTER testing will be a lot more useable in your reloading life, than the internet evaluation before testing. Load some up, and tell us how it turns out.
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So true, so true...
 
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