9mm vs .38 bullets

G

GTNMUDY

New member
I am having trouble finding 100-115 gr lead cast bullets for my .38 special in my area.

Found some 9mm cast bullets in my area.

Since the dia of each bullet is 9 mm (+/- .003mm), any issues using them for my reloaded .38's?
 
The 9 mm is nominally cast at 0.356" while the .38 will nominally be 0.358". That doesn't seem like much, but with lead bullets even the smallest gas leak can spray lead onto the barrel. Also the bullets tend to unbalance because they tend to bear against one side of the bore so the rifling cuts 0.002" shallower on one side. A friend of mine had an improperly manufactured .38 barrel that had rifling lands 0.006" tall on one side and 0.002" tall on the other. All bullets he tried were unstable and tumbled and keyholed and threw turkey platter size groups at 50 feet. I realize that's twice the difference you are talking about, but I wouldn't expect you to get good results based on the principle.

The only remedies I am aware of if you have to use such small bullets, are to, 1.) buy them soft, like swaged bullets, and fire them with a very fast powder, like Clays or N310, that will bump them up to full diameter with the sudden pressure impulse; 2.) squash the bullets slightly shorter and fatter in a press, then run them through one of the inexpensive Lee bullet sizing dies for .38/.357 on your loading press, though this won't provide great consistency but will eliminate some of the worst trouble. If by some miracle the bullets don't tumble badly from uneven rifling engraving, then you might prevent the worst of the leading by cutting base wads for them from low density polyethylene (LDPE) sheets. That will act as a gas check.

Sorry the news isn't better.
 
It depends on how those bullets were sized. In theory, 9MM groove diameter is about .356", some say .355". I've slugged the barrels on three different 9MM handguns and groove diameter has run .357" to .3575". If those light weight bullets are sized for a .355/356" groove diameter, I'm betting they lead like hell. All you can do is buy the smallest amount they sell and try them. Maybe they'll size them .358" and preferably .359" for use in your .38 Spl.
Paul B.
 
I would say give it a try if it were the other way around. I have seen several 9mm guns that lead built up in quickly with commercial 9mm cast lead bullet. They switched to a very close bullet for .38 special that worked like a charm to stop the leading, and shot true to the sights.

Under sized bullets will shoot out of your gun. They will not blow things up. It can be done. Just be prepared to do a lot of work to clean it out. Also expect the bullets to key hole badly.
 
Heck, if you can't find those bullets locally, just get them online like most of us.
It shouldn't be hard at all to find a wide variety of lead bullets, whatever you like to use.
No big deal, especially with the low cost shipping now available.
See how simple life can be?
 
Thanks for the info.

I am setting up my wife with a 38 special and wanted to go light loads for her to get use to the gun.

About the lightest bullet I can find locally is 158 gr cast.

Once she is carrying it it will be loaded with factory defense ammo.

I am not expecting good accuracy as it only has a 2'' barrel.

Close range for sure.
 
I cast Lee tumble lube 158 grain semi wadcutters for .38/.357 Supposed to drop .358. Usually end up a little bigger.

I also cast Lee tumble lube 125 grain round nose for 9mm. Supposed to drop .356. I noticed some were .358, so I separated some and loaded them up in .38 special cases. I kept the same charge I use for the 158's.

Seemed to shoot fine out of my S&W 637 snubby. Fairly accurate, no increased leading.

As far as the 2" barrel, you'd be surprised at the accuracy you can get. My little smith shoots great.
 
Undersize lead bullets are a big source of barrel leading.
I had two 9mm in .38 combinations that would work, but it is not something I would bet on.
 
I have extensive experience using 9mm Luger bullets in 38spl/357mag cases shot out of an SAA Pietta 357 magnum revolver.

Cast bullets only. FMJ 9mm Luger bullets somehow are to small.
Cast bullets.
I use Lee molds. I DO NOT SIZE ANY CAST BULLET. Use them as cast.
The .356“ diameter 124 grain Lee Truncated Cone lead bullets lend themselves very nice for Nagant style deep seated bullets in 38 spl cases loaded with the same amount of powder than 9mm Luger rounds with these bullets. You have to shoot them out of 357 mag guns.
Those are kind of Nagant style Wadcutters. They do not lead more than normal. Actuallly I never clean the bore of my revolver.

As soon as I got my molds I switched to 148 grain Lee Wadcutters for the 38spl/357 mag cases seated Nagant style deep as well loaded to 9mm Luger pressures.

If you dont want to seat them Nagant style deep you can make yourself as well 9mm Federal Rimmed cases from 357 mag brass. That gives you an 9mm Luger rimmed for revolvers. I found these to complicated to make and switched to Nagant style loading.
Check out threads on TFL. I posted various.
 
Quote:
Since the dia of each bullet is 9 mm (+/- .003mm), any issues using them for my reloaded .38's?
Did you make a typo? .003MM is only about .0001 of an inch.

Yes, I did. .02 mm

The 9mm are .355 and the 38's are .357.

Was asking if that .002 of a inch would make a differance in my 2" revolver at close range.
 
The 9mm are .355 and the 38's are .357.

Was asking if that .002 of a inch would make a differance in my 2" revolver at close range.
Click to expand...
Possibly...although it was a rifle, I had a Winchester Legendary Frontiersman in .38-55 with the "traditional" bore size of .379 and the mold I had was dropping them at .377. Nevertheless I found that if I used a very soft alloy, they would bump up and fill the bore producing decent accuracy. You may get away with that (try a soft alloy), with your revolver and find out if it works.
 
Lots of bullet casters found on the Net. Just a matter of contacting one and placing a order. No guessing then if this or that will work. Just asked the caster what he suggests for a 38 Specials light weight bullet.
 
Code: 
Was asking if that .002 of a inch would make a differance in my 2" revolver at close range.

It's possible, depends on your bore size, alloy, and load. If I was set on developing a 38 round with that bullet, I would make a bunch and separate by size so I was starting with at least .357. I would then powder coat them and not size them. This could get you up to enough size that the bullet will be accurate.

You may be able to order cast 9mm bullets that aren't sized and could be powder coated.

If I were you I would order a small batch of 140-148 grain .38 lead wadcutter bullets. These are normally set flush, use less powder and are soft shooting. Try a couple of powders at starting load and shoot them for accuracy. If my wife were leery of a soft shooting wadcutter load, I would not load her revolver with defense loads.

I have a soft shooting green dot load that my wife has shot and that is what the revolver stays loaded with. I would feel comfortable carrying my snubby with wadcutter loads. (mine are 158 grain lead semi wadcutter)
 
Well, the reason I mentioned factory defense loads is that I have heard that if you use reloads for self defense you could be in a lawsuit for making a special bullet that would gravely harm someone (no sh1t, you want him dead).

Besides that I told my wife that when and if it comes to that you won't feel or hear the shot because you will be so pumped up.

Just like your first shot at a big buck on opening day.:D
 
100-115 grain lead cast bullets are little fellows for a .38 Special. Might be why you can't find 'em. Not enough demand. .355" bullets of that weight(the 100's anyway) are likely for .380 and don't work well out of a 9mm.
"...if that .002 of a inch would make a difference..." A lot depends on the hardness of the lead. A .356" bullet might expand enough.
"...if you use reloads for self defense you could be in a lawsuit..." Mr. Massad Ayoob, a very good guy, promulgated that years ago. Any competent defence lawyer will refute that line of argument in seconds. "Your honour, my client was using reloaded ammunition to increase the accuracy of his shooting. Thereby reducing the chances of an errant shot hitting an innocent bystander."
In any case, if you shoot somebody, dead, you could be in for a law suit too. Even if the bad guy was a life long, known to Police, professional criminal, his next of kin can sue for wrongful death.
 
yeah, ain't it the truth...

You buy a gun to protect yourself, take a class to make you good at it, honor all the laws, register your gun, pay your taxes, have a job, kids, car and a home and some low life with a stolen gun will try to take your life and if you defend it then sue you for all you got.

Ain't life good...:mad:
 
Isn't .003mm equal to 0.00011811024" or less than a tenth of a thousanth of an inch?
What am I reading wrong?
I have several fine measuring devices, but none are that accurate.
 
Last edited:
Isn't .003mm equal to 0.00011811024" or less than a tenth of a thousanth of an inch?
What am I reading wrong?
I have several fine measuring devices, but none are that accurate.

You must have missed my post admitting I was in error. Too many 0's

Or are you starting this all over again :confused:
 
You must log in or register to reply here.
Back
Top