cast for .357 SIG

[Boolseye]

I'm coming up empty in my searches for this topic. Perhaps that should tell me something–but I have the gun, and the dies, ergo I need a boolit. I have the Lee 120 TC standard lube–best bet? I also have the NOE 358-135. Anyone who casts for this round, please weigh in.
-BE

[runfiverun]

put a couple in some empty cases and see how they feed from the magazine.
maybe start the oal a bit long and shorten it a tick and see what feeds and ejects the easiest.
then just start low and work up till you get 100% function of the gun.

there is your baseline load to build from.

[drw]

Saeco 377 is what I have used for years. I have tried others but the Saeco bullet has the extra long body for the short neck 357 Sig cartridge.

[Boolseye]

Thanks guys. That Saeco looks close enough to my Lee that I imagine it'll work.

I can only envision hot loads with this gun. I think I would prefer something in the 130-150 gr. range, capable of 1200 fps with accuracy. Otherwise, why bother? the luger covers everything else.

[Elkins45]

The main factor in choosing a 357 Sig bullet is to get one with a decent amount of straight sided bearing surface so it gives you decent neck tension. Because of the bottle neck I find that almost any nose shape feeds OK. Your biggest worry is getting enough tension that you don't have setback when it chambers. That's a reason to aim for 100% load density too, because the powder doesn't give the bullet anywhere to go. AA#9 is a popular choice for that reason.

[Boolseye]

I see. Thanks for the explanation.

[Andy]

I am not an experienced reloader/caster but the only cartridge I own but don't reload for is the .357 sig out of about 10 cartridges. The two reasons for this are the neck tension thing and my perceived risk of the .40S&W case bulge issue going on with the .357 sig cartridge. A visual inspection of my factory glock .357sig barrel shows it is definitely not supporting the case in the same way the .40S&W guys worry about for that cartridge. You may want to read up on this if you haven't already. I am sure there is a safe way to do it, but I know it is a much more risky round to reload than average due to these two factors.

I figure I'll reload it someday, but only after i learn the ropes on the more forgiving cartridges.

[Boolseye]

Thanks Andy. I was looking at the accurate molds, the 35-147S or maybe the 35-125S.

[james nicholson]

I have cast and loaded for 357 Sig for some time now, Elkins 45 said it all. Straight surface, long enough for a good grip and 100 % load density. I use the 120 grain Lee truncated cone mold and 13 gr of AA-#9. Sized at .358 and lubed with Lars' BAC lube. This works fine in my Sig 250 and my Glock Gen 4 32.

[Chris24]

I have been loading 357 Sig for years, and haven't had any major problems. I found that using a .40S&W carbide sizing die before the 357 sizing die keeps me from having to lube cases. Usually I use 124 grain plated TC bullets.

I just started casting for it, and use the Lee 120-TC also. They drop at about 125 with my WW alloy. The bearing surface is a bit short on it, so i use an OAL of 1.16" to make sure the neck is good. My Glock mags have no trouble with that length. I like to use AA9, Power Pistol and Blue Dot for my plinking loads. Longshot is good for the really hot loads, up around 1500 FPS.

[Boolseye]

Good info. Thanks folks, keep 'em coming! I'm also interested in hearing how people feel about the round in general, what they like about it, accuracy, etc. Also what you don't like about it, if that's the case. I haven't shot it yet, so I have no opinion. It kind of intrigues me and I have the barrel now for my m&p .40. I'm leaning toward a heavy, 147-150, that'll also work in the 9.

[Beef15]

I have cast for my M&P 357. I want to say the barrel slugged .357, I sized to .358. Using wheel weight alloy and the Lee 120TC with AA9 or Power Pistol it leaded horribly. Toyed with PC @ .356 for a hundred rounds, no leading, recoil seemed harsh, need to experiment more.

Was looking at that NOE 135 today, looks like it's made for the Sig... I got the 155TC for my 9mm, but will probably add it soon.

If you don't have dies make sure you get a set with an expander, you have to have one for lead. RCBS dies don't come with one. Also crimp seperate, the only time I buckled shoulders was trying to crimp and seat in one die. No set-back or tension issues.

One thing about the M&P, everyone talks about 357S OAL length needing to be short to fit mags, that does not appear the case in this gun, the throat is my only real limit so far.

[goste]

I'm also getting to have some interest in the .357Sig. since this is a bottleneck round, does it use a taper crimp, or roll crimp? I hear talk of bullet setback, hence the advice to use AA9, for case fill., but I was wondering if one could use a tumble lube boolit, and roll crimp in one if the micro bands.

I have yet to find a platform in .357 sig, that I want to purchase. I have a lot of brands in 9mm, and.45, but would like something diff., for .357 Sig, just don't know what it would be yet

[osteodoc08]

Initially I was told to steer clear of cast boolits for my 357 Sig. I dont shoot it as much as I once did. I ended up loading 124gr XTP and the 124 TC double plated boolits.

It is common practice by many to size the body of the case with a 40/10mm sizing die.

Be sure to not set back the shoulder too much or you will have FTF since the case headspaces on the shoulder (making a long reach for the FP to primer)......ask me how I know.

You boolit choice must have a long body as mentioned due to the bottle neck design. Another reason I have steered clear of cast boolits, but I'm sure there are plenty of options now days.

I've always used AA#9 for my 357 Sig loadings. My XTP's literally rest on the powder column and cant set back.

I initially didnt even want to mess with the 357 Sig but my lovely wife (SWMBO) bought me a Glock in 357 Sig as a gift. I have learned to love it and admire the cartridge for what it was designed to do........Mimic the velocity of the 357 Mag with a 125gr bullet. That it does. It is far outpaced with heavier loadings, but does favorably with the 125gr class bullet.

[bstone5]

Load the 357 SIG a lot. For a SIG that can use the 40 S&W barrel or the 357 SIG barrel.
Bullet is the Accurate 35-120G.
I designed the bullet using SolidWorks.
Accurate made a two cavity mold out of steel to fit my Master Caster.
The bullets are powder coated to as not to require lube.
AA #9 powder is used to help remove set back.
A Lee crimp die is also used to apply a crimp at the end of the case.
Shoots very well, have shot several thousand without problems.

[chucky64]

Here are the two bullets that I use to reload the 357 sig cartridge. The saeco 377 and the Lee Bullet Mold 358-125-RF. Now day's I mostly use the Lee mold, being a 6 cav a lot of bullets can be cast in a shorter
amount of time. It took a long time to get the dies set up perfectly so they load, function and grip the
bullet to my satisfaction. My personal favorite powder is Acc # 7, When the crimp die is finally set up
correctly I dont feel the need to fill the case with the slower powders like Acc#9 to prevent setback.
Attachment 167104

[Boolseye]

Looks good. Thanks for taking the time to post the pics. I'll have a good knowledge base when I get up and running.

[runfiverun]

if you want to slow things down and not make 1killion mph loads for it.
you could step the powder back in speed and get on the too slow side of things.
in my 25-20 I went to AA-2230 powder and just kept on adding more until I was happy with it.
I used AA's 1680 data to work from.

[Boolseye]

step the powder back in speed

Runfive, do you mean lower the charge or use more of a slower powder?

[warboar_21]

I haven't bought a mold yet for my Sig. So far i've been using Hunter's Supply 125gr bullet. I've used both AA#7 and #9. My 229 shoots this bullet with no leading and accuracy is very good. I have been thinking about picking up a mold to feed it though.