loading .357sig

[five.five-six]

I bought a glock 23 the other day because well, it was cheep and I already load fo-tay and it came with a .357sig barrel and I love shooting .357sig besides I already have dies and projectiles and brass for loading .357sig....except that it turns out that I don't.. I must have included them when I sold my 229 but I digress.

Getting dies, conversion kit, powder measure etc is just a matter of money. It's finding projectiles that is driving me nuts. I'm cheep so I'm looking for bulk possibly plated but I remember that standard RN 124's don't work well in .357sig. I'm looking for .355 FN or HP, any ideas?

Also, I know I can load with bullseys but it's not really optimal. I have bullseye, WSF and 296 but I suspect I'll have to buy another powder.

I know BE will work but first I need to find bullets.

[TomReloaded]

Rmr has them. They're cheap and good. I've shot thousands. https://www.rmrbullets.com/shop/bull...t-matchwinner/

If it works in .40 and 9, itll work in 357sig (powder). Nothing special needed.

[five.five-six]

Rmr has them. They're cheap and good. I've shot thousands. https://www.rmrbullets.com/shop/bull...t-matchwinner/

If it works in .40 and 9, itll work in 357sig (powder). Nothing special needed.

Nice price on jacketed 124s.


Out of Stock - Backorder Okay


I do like your logic, if it works in .40 and 9mm its good for sig... of course, you push a .357sig a helavalot faster than either of those.

[Swagman00]

Lee #90238 124 gr cast, works awesome with straight wheel weights, use alox and keep velocities around 1100. Above that, Alox with wood wax, paste wax, beeswax helps. Several powders are listed for lead conical in AA PDF.

http://www.accuratepowder.com/wp-content/uploads/2018/11/WPHandloading-Guide-7.0-Web-REV.pdf

[slixx1320]

xtreme has copper plated 124g FP available.

https://www.xtremebullets.com/9mm-124-FP-p/xc9mm-124fp-b0500.htm

Or you could pay a bit more for 125g FMJ-FP

https://www.wideners.com/reloading-supplies/bullets/pistol-bullets/357-sig-bullets#zero-bullets-9mm-355-inch-diameter-124-grain-fmj-500-projectiles

[2Asupport]

HI, I am also just getting into loading 357sig. Once you decide, please let me know what powder you choose. I know it mostly preference and desired muzzle velocity, but I have no idea what to narrow down to. (Blue dot, Unique, Zip...)

Thank you for any advice.

[five.five-six]

HI, I am also just getting into loading 357sig. Once you decide, please let me know what powder you choose. I know it mostly preference and desired muzzle velocity, but I have no idea what to narrow down to. (Blue dot, Unique, Zip...)

Thank you for any advice.

[maxx03]

Powders for 357 Sig

Blue Dot, Longshot, AA7, AA9 and Unique are a few powders I have used with 357 Sig.
Longshot gives me the best velocities with 124 grain HAP Hornady bullets.
Make sure to get a taper crimp die.

[five.five-six]

Blue Dot, Longshot, AA7, AA9 and Unique are a few powders I have used with 357 Sig.
Longshot gives me the best velocities with 124 grain HAP Hornady bullets.
Make sure to get a taper crimp die.

[jdmacl]

I've loaded and loved Barry's Bullets 124 gr. and Power Pistol for years.

[five.five-six]

Well, I got all the parts for the 550, I got brass and 115 grain JHPs.

The only powders I could come up with are blue dot and green dot. Any ideas on recipes?

[slayer61]

Start with recipes for 125 grain. They will work to get you started with 115s

[BajaJames83]

357 sig can be rather rewarding when you reload it as you can do it for the cost of 9mm and make some killer loads.

[Corbin Dallas]

Well, I got all the parts for the 550, I got brass and 115 grain JHPs.

The only powders I could come up with are blue dot and green dot. Any ideas on recipes?

I've used unique, reddot and bullseye in the past. I like reddot because it fill the case. No chance of a double charge.

BTW, don't go with 115's. (example - 115g with bullseye = 8.0g, 124g with bullseye = 7.0g) Pressures are around 37,000 with both and the speed is right around 1400FPS.

FYI - Bullseye and RedDot no longer have load data for the 357SIG on alliant's web portal. Unique is, but only for 125 and 147g .356 projectiles.

https://www.alliantpowder.com/reloaders/powderlist.aspx?page=/reloaders/powderlist.aspx&type=1&powderid=3&cartridge=24

What you want is .356 125g TN

http://montanagoldbullet.com/357sig-125gr-fmj-100ct/

Now, here's the part you really need to know and I'm telling you because I've loaded 10's of thousands of 357SIG.

#1 - Case setback is the real deal. I load to 1.14 even if the manual says 1.135. If the bullet gets set back in the case, even slightly, you run a very high risk of increased case pressures and possibly a rupture or KB that could destroy your barrel, firearm and your hand.

SAAMI case data for 357SIG - I HIGHLY RECOMMEND READING THIS and pay special attention to page 185.

#2 - Start with a reduced load and work your way up. 10% less is not a bad start.

#3 - Make sure you are not under crimping or over crimping. Under crimp could lead to bullet setback, over crimp could increase case pressures. Really important.

#4 - If you have the space, install a powder check on the press or at least have a really bright light so you can see that each case has the right amount of powder and don't let your hopper run dry.

#5 - Meter your hopper often to ensure you're getting good metering. Nothing worse than expecting 7g and getting 7.2. In these cases, it makes a huge difference. You're basically loading a necked rifle case for a pistol.


Go forth and prosper!

[Sandspider500]

800x, power pistol, or longshot