Reloading .357 Sig

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I'm going to start reloading .357 Sig. I will be using a G-23 with a Barsto .357 barrel. I have questions about what powders, bullets, dies to use. I am reloading for several pistol calibers already, so any input will be appreciated. Thanks.

[ar15barrels]

Any brand of dies is fine.

What does your reloading manual say about powders and bullets?

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I am looking for recommendations on powder/bullets.

[ar15barrels]

I am looking for recommendations on powder/bullets.

What does your reloading manual recommend?

There are some bullets that are more appropriate to the 357 sig.
Look for them to have a longer bearing area and a shorter ogive.
This will allow you to seat them to magazine length and still get a crimp on the bearing area.

Pointy bullets end up seated with some of the ogive in the case mouth and occaisionally one will get deep seated all the way down into the case during feeding.
Definetly not what you want.

[buffybuster]

Stick with 115 or 125gr Tuncated Cone type 9mm bullets. As Randall stated, you'll be able to seat the bullets to proper OAL and still have good neck tension.

[C.G.]

I am looking for recommendations on powder/bullets.

Before I type out the whole .357 Sig reloading manua, what grain bullets are you thinking?

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I thought about a 124 or 125 grain bullet. I was wondering about Rainier's 124 gr FP. I have used Rainers in 10mm up to 1200fps with no problem. Do I need to go jacketed above 1300/1400 fps? If so, which one?

[C.G.]

From Speer manual

Speer 125 TMJ

AA #9 starting load 13.1, max load 14.6
Blue Dot 9.9, 11.0 compressed
AA#7 11.1, 12.3
Unique 7.2, 8.0

From Complere Reloading Manual for the .357 Sig

Sierra 125 JHP

Unique starting load 6.0, max load 7.7
AA#7 8.6, 10.5
AA#9 10.0, 12.0

Disclaimer: use at your own risk and always work up a load from starting load. Do not exceed maximum loads printed in bold.

Sorry, do not have any data on Raineer, I use Speer bullets. I have used AA#7, AA#9 and Blue Dot. Blue Dot seems to have more flash.

Good luck.

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Thanks for the help.

[BSlacker]

Berrys makes a good plated 124gr bullet for the 357 Sig it is available in HP and FP. The HP has a little longer bearing surface.

http://www.berrysmfg.com/9.php

I have pushed these to 1360fps without any problems although most of my loads run around 1250 with plated bullets.
Check out the Lee factory crimp die (FCD).
Lots of good loads from the powder people. AA#9 is popular it fills the case and people think it cures the set back issue. I don't want to depend on powder to keep the bullet set and it is a fine grained powder that leaks out of my powder measure. I have good luck with HS6 and W350.

[Corbin Dallas]

Any brand of dies is fine.

No, they are not fine.

When dealing with case pressures of 60k+ spend the extra money and get quality carbide dies and a lee factory crimp die. (BTW, I have a spare 357SIG Dillon Carbide die set available for sale if you're interested)

I personally load 7.0-7.2g of Unique behind a 125g Truncated Cone .356 FMJFP round. I have used PMC, Montana Gold, Berrys and Rainier. My next batch will be with Montana gold.

Some issues I've found with Berry's and Rainier are the plating is too soft and gives a bit under pressure. If you tighten the crimp, it only smashes the bullet at the neck which is a bad idea.

2 things you absolutely do not want to happen:

1- Bullet setback. This will surely cause a Kaboom. Case pressures are high enough. Add bullet setback and the pressure increases exponentially.

2- Overcharging. With plated bullets like Berry's and Rainier, be sure to drop the powder load by 10%. Also, if your press is capable of warning you of under or over charging, use it.


My .02 from loading nearly 10k 357SIG = GO SLOWLY and check every single round in a case gauge. Be sure your OAL remains constant and check your powder weights frequently (every 50-100). Last thing you want to do is loose a finger.

[halifax]

This is what I've loaded for IDPA.

Dillon carbide sizing die
Lee factory crimp die (a must because of setback)

124gr Rainier Ballistics 9mm CPFP
WSP Primers
5.5gr AA #2
1.140 OAL

Again, this is a weak load for IDPA. I have used as much as 9.2gr of Power Pistol to drive the same bullet to 1430fps but I don't recommend it. Start at 8.0gr if you are going to try Power Pistol.

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Thanks for all the information everyone.

[Telperion]

I started off with AA#9 because people said it filled the case and was perfect for the round. I found it to be too slow, and noticed unburnt powder sprayed everywhere. I found powder granules all over my chronograph 10 feet forward of the muzzle.

Now I use VV 3N37, with a load of 8.4 gr behind a 125 gr FMJ (Montana gold bullet). This duplicates the 1300 fps I get from Speer factory ammo out of a 4" barrel.

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Reloading .357 Sig Reload this Page Reply to Thread

Well, I got my Starline brass, 400 Hornaday 124 gr. XTPs, and 500 Rainier 124 gr FP, Lee Dies, and a Lee FCD. I started setting the dies up and I ran into one problem. I tried to just chamfer the inside of the case and not bell it. It didn't work with my setup. The bullet would fall over and crunch the case mouth. I tried chamfering and .003 bell on the case. I got .004-.005 bullet setback every time I loaded the round. So I just resized them in the Lee die to a neck size of .374 and went with a bell of .003 and it worked. I chambered the dummy round up to 5 times with NO bullet setback. I set the crimp for .378. This leaves a light line on the bullet which is consistant with my 10mm crimp on Rainier bullets. I am going to start reloading tonight with the plated bullets. I have some Blue Dot, N-105, and 4# of AA-9. I think I will get rid of the Blue Dot and N-105 first. Thanks for all the help. I'll let you know how it goes.