357 Sig reloading data

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SteelManCM

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Looking for some reloading data for 357 Sig. I use bullseye powder and cast my own bullets. I can size my 9mm casts to .355 without an issue. Will I need to get new dies? How many grains of powder. I haven't found much at all on this caliber. Thanks in advance for any help.
 
http://data.hodgdon.com/main_menu.asp

That should give you all the information you need for every powder and bullet made. As for cast bullets, Im not sure. As for the dies, you will need a new set.

DFisher3112
Wow. Don't know how I missed this. GREAT site! Thanks.

Kinda figured about the dies, but had to ask. Thanks for the resource.
 
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Before sizing your bullets to .355, slug the barrel of your
pistol, and size .001 over the groove diameter. You will
save yourself from experiencing leading, or at least, you
will have minimal leading.
 
Nice tip. Although, generally, if I find a round I like, I have more than one gun in that caliber. I guess the best would to be to slug them all and average it out. You've got me thinking. Thanks for that.
 
Are you asking if you need new dies to load the 357 SIG ... if you do not have any ... then, yes you will.

If you are asking if you need different dies to load 357 SIG LEAD... then no... if you already have a set of 357 SIG dies. You may need a different bullet seating stem with a profile to match the lead bullet better ... then you may not either.

http://www.alliantpowder.com/reloaders/default.aspx
http://www.accuratepowder.com/reloading.htm
http://www.lapua.com/fileadmin/user_upload/esitteet/VihtavuoriReloadingGuideEdition8.pdf

Jimmy K
 
Yeah, I guess I gave incomplete information. Sorry. I currently load:

.32ACP
.380ACP
9mm
.38/.357
.40S&W
.44sp/.44Mag
.45ACP/.45LC

I know that the .357Sig uses the "same" (.355 vs. .356) projectile as the 9mm, but due to the bottleneck of the cartridge, I believe new dies are necessary. Although, if they are not, then I can get started sooner.

Thanks again for the information.
 
You will need a set of dies, also you will need to lube the cases
because of the bottleneck. I use imperial sizing wax, and a little
goes a long way. You can get it at Midway or other online vendors.

I have also used Hornady One shot...but I am cheap, so the Imperial
gets the nod.

Data for lead is a bit scarce. Most data shows jhp bullets, which
are much stronger than lead or plated bullets. You will probably
need to keep velocity under 1200, unless your bullets are sized
properly.

Which mold are you casting? I have shot the Lee 120
truncated cone out of my 38 super and 9mm. It is accurate in
both guns. I can shoot them as cast...they are falling at .3565
to .357. As cast diameter, as I am sure you know, will vary based
on your alloy, etc.
 
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