resize .357 brass in a 9MM die?

[fjlee]

I reload and shoot .357 mag. I only use WW brass, which has a consistent wall thickness at the mouth of the case of .0105 inch to .0115 inch.

I shoot only JHP 125 grain bullets, and I really like a lot of “neck tension” gripping those bullets.

I use RCBS dies, and when I resize that WW brass, I do NOT use the expander ball……in the interest of getting a good tight inside diameter of the brass case. Using just an absolute bare minimum of case belling, I can seat .3570 inch diameter jacketed bullets cleanly. No shaving at all, never a collapsed or wrinkled case.

I’m wondering about getting an even tighter fit……by a thousndth or 2.

Anyone here tried resizing WW .357 brass with a 9MM resizing die? Seems like since jacketed 9MM bullets are nominally .355 inch diameter, that the 9MM resizing die would size down a .357 case to a tiny bit tighter inside diameter than would a .357 die.

Super tight neck tension gives _SUCH_ a clean powder burn, even on reduced loads.

Comments? Additions? Am I overlooking something?

Thanks, folks…… FjLee Denver CO

 

[rfwobbly]

The 9x19 is a tapered cartridge and I think those dies would mess you up big time. If you insist on this project, then you might have better luck with dies for a 38 Super (aka 38 Super Auto), a straight wall auto cartridge. If you just want to resize the last .200" of the case mouth, then 357 Sig dies might also be worth looking into.

If all you want is 'clean burning on reduced loads', then the easiest way to get that is to use slightly faster powders. Take a look at a powder burn chart Like This One Right Here.

 

[rcmodel]

I can't imagine needing more neck tension then you already get with unexpanded .357 brass fresh out of the sizing die.

It will only stretch so much without cracking when you seat a bullet.
And it's already stretching nearly that much now.

rc

 

[Jim Watson]

And if you looked at the dimensions of the cartridges mentioned, you would find that a 9mm P is nominally .380" at the mouth, a .38 Super is .384", while a .357 Magnum is .379".

So using another caliber's sizing die would give less reduction and lower bullet pull, not more.

I've loaded jacketed .38 and .357 by resizing normally and flaring with a plug that does not expand the case neck below that little bit of flare. Works fine, as the OP says.

Elmer Keith reported using a small diameter expander to get good bullet pull in .44 Magnum.

 

[mackg]

Actual diameters of sizing dies are hits and misses, apparently only randomly related to cartridges specs.
LEE usually aims at good looking ammo close to specs, which might not have enough neck tension; while others will deliver cartridges with that "bottle of coke" look ( Hornady nitride(?) come to mind...).

So I would look at recently produced dies, and bins of used tools in stores or gun shows, with a way to measure their rings.
Aim for a 38/357 die, or a straight cartridge; a 9mm or 38 Super die will leave a donut at the base of the case, preventing chambering.... or you can try neck sizing after your regular die.

 

[Seedtick]

Or.......

Maybe you could just try sizing a couple with your 9mm sizing die and see how it does?

Please let us know what you find out.

Seedtick

 

[unknwn]

There is an FCD available for that cartridge that uses the collet style of crimp.
You can get it through ONLY one source. You would most certainly be able to tighten up that fit without the drawback of the standard roll crimp available with any other die.
http://www.ranchdogoutdoors.com/index.php?main_page=index&cPath=53_54

 

[zxcvbob]

I tried a .38 S&W sizing die when loading .38 Special wadcutters. (.38 S&W sizer is the same as .38 Super) It worked just fine for thick-walled brass, but with Remington brass there's not enough neck tension.

You might try neck-sizing with a .380 sizing die, but I would not expect that to work very well. (I've done that with .45 Colt, neck sizing with the base of a .30-06 die)

 

[kingmt]

It's brass. You can only get so much press fit. Any more just resizes the brass & over works it.

 

[dickttx]

I recently got a 38 Super Commander and new Lee dies. I found while measuring the OAL, rolling my micrometer would push the .355 FMJ bullet further into the case.
With the help of some kind folks on another forum, I started sizing and depriming using my 38 Super die. I then put my 9mm sizing die in my turret, adjusted to where it only sized about the top 1/4" of the case, and proceeded to reload normally. Had very good results with that.

 

[RainDodger]

First of all, I would question why you need more neck tension, and then I'd think about pressures. My boring advice it to stick to the manuals and stick to the proper dies.... unless you're seeing a problem.

 

[BSA1]

If you are shooting the same brass for the same gun there is no need to full length resizing.

 

[murf]

size in a normal 357 die. size in a 9mm die. bell the case mouth with a 9mm die.

the expander plug in the 9mm die is .353" in diameter. the plug in the 357 die is .356" in diameter. the expander plug in the 9mm die is a little short, but should do what you want.

the thin neck walls of the winchester cases are a pain and don't give very good neck tension.

murf

 

[zxcvbob]

Size and deprime with a normal .357 die, bell just the very end of the mouth with a Lee universal expander die (you should have one of these in your toolbox anyway.) That will give you the maximum neck tension without doing anything weird.

Don't go overboard on the crimp; it can bulge the cases and loosen the bullets.

If all this is just to get a cleaner burn, you can also do that by using a faster powder -- Red Dot, American Select, Solo 1000, PB, Clays, etc.

 

[GLOOB]

the thin neck walls of the winchester cases are a pain and don't give very good neck tension.

That's been my experience with W-W 45ACP cases. But OP's measurements don't indicate that his brass is thin, at all. None of my 357 brass is that thick. I'm getting 0.0090-0.0095 on my Winchester and GFL 357 case mouths.

 

[joneb]

I bought some RCBS carbide 9x18 Makarov dies the expander/flare plug diameter was .362" which fine for .365" bullets. I wanted another plug so I called RCBS and they sent one at no charge
I chucked the plug in the drill press and took it down to .360" for .363 and .364 diameter bullets.

 

[evan price]

What sort of crimp do you use? I have best results with a good roll crimp and a standard 357 die set. Neck tension or crimp will both give enough delay to let pressures build in the case before the bullet moves.

 

[fjlee]

What sort of crimp do you use? I have best results with a good roll crimp and a standard 357 die set. Neck tension or crimp will both give enough delay to let pressures build in the case before the bullet moves.

Using an RCBS roll crimp die, I apply a roll crimp in a separate operation.

FjLee Denver CO

 

[fjlee]

If you are shooting the same brass for the same gun there is no need to full length resizing.



I'm shooting a revolver. This revolver has 6 chambers.

FjLee Denver CO

 

[Hondo 60]

rfwobbly & rcmodel are both correct.

9x19, 9mm, 9mm Luger, 9mm Parabellum, no matter what you call it, is a tapered case.
You don't want a tapered case for 38/357

 

[James2]

I’m wondering about getting an even tighter fit……by a thousndth or 2.

Are your bullets moving as you shoot? If not, why do you need more tension? I am not convinced that neck tension has much to do with pressures or clean burning.

It is probably best to use the tools designed for the job and according to the instructions supplied with those tools.

 

[kingmt]

A carbide die won't make the case tapered. It would be more like a bottle neck until you seat the bullet.

 

[fjlee]

why do you need more tension? I am not convinced that neck tension has much to do with pressures or clean burning.



My opinions on the pressure part of your comment would be pretty weak and mostly "un-provable" by me....., so I won't address it.

But as for the "clean burning" part.......I've demonstrated to MY satisfaction.....many times over......that increased neck tension on my 125 gr. JHP bullets indeed does give a cleaner burn.

The fastest powder I've used for my experiments was Red Dot. I've also worked with the OLD OLD Unique. Also Green Dot and IMR SR4756. Cleaned all of 'em up noticeably as I increased neck tension.

The slowest powder I've used for these experiments was Blue Dot, way back in the day when it was okay and accepted to use Blue Dot with a 125 gr. jacketed bullet in a .357.
Cleaned it up.

Decreasing the ID of the brass case at the bullet seating area is one way to increase neck tension, obviously.

Another way that was interesting to me was to use a "bullet sealant"...commonly used if ya want to waterproof your cartridges. I had some primer/bullet sealant, from Herters a looong time ago, that I used in a couple of experiments. It was a messy, time consuming experiment, but it certainly quickly showed me that WITH the sealant, the powder burn was cleaner.

There are a couple of other advantages to having a VERY firm "bullet pull".....but I really don't want to incite people to a lot of arm waving and foaming at the mouth.

BTW, I _AM_ enjoying these experiments, and as a happy by-product.......usually but not always......when I get a cleaner burn, I'll get a small reduction in group size on a paper target. Possibly due to more consistent velocity, or a lower SD.......or both. Not sure, as I don't have a chronograph.

FjLee Denver CO

 

[gamestalker]

+1 RC

 

[murf]

fjlee,

a little footnote to post #13 above: the 9mm sizing die i use is an old steel rcbs. the carbide sizing dies won't work. with that steel die i get an extra .002" reduction in diameter with that die, down to .373".

with .010" case neck dia., the i.d. is now .353" instead of .355". i run it in a .354" expander plug and get .003" neck tension instead of the normal .001".

murf