.357 Sig Difficult to Reload?

I've been reloading for about a year now. I reload a number of different calibers, but haven't tried .357 Sig. I've heard it is more difficult to do but don't really understand why. I'd appreciate any feedback from people experienced in reloading it.
Thanks!

I bought the Lee dies and the separate bottle neck cartridge die. I’m not sure why they market them separate and don’t have a four pack kit like the rest. So far they look good. I have yet to try them yet though. Problems I heard when I first started was not using proper bullet selection and not seating to the right depth. You need bullets with a proper baring surface.

baxtersmith said:

I've been reloading for about a year now. I reload a number of different calibers, but haven't tried .357 Sig. I've heard it is more difficult to do but don't really understand why. I'd appreciate any feedback from people experienced in reloading it.
Thanks!

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Since the 357 Sig headspaces on the case mouth like the 45 ACP or the 9mm Parabellum etc. you need a good grip on the bullet. The original factory loads from Federal solved this by glueing the bullets in place[they and others may still do it today]!
So . . you can't expand old cases too much or you'll not get enough grip and the only real 'crimp' would be a taper type. Using new cases with just a slight belling at the mouth of the case may resolve much of the grip issue - but I'll bet its trial and error.
Additionally, if you start loading 'hot' you'll have to be sure that rounds further down in the mag don't start having bullet setback and the subsequently higher pressures associated with this issue. I've based this just on my readings - I have all the cases and dies but I've never gone forward with it and just stuck with factory ammo.
We'll see how others respond on this. Just my $0.02!

Since the 357 Sig headspaces on the case mouth like the 45 ACP or the 9mm Parabellum etc.

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This is generally what you will read, but that hasn't been the experience of most folks loading for the Sig. I load for 3 different Sigs and there is way too much variation in the throat length for it to headspace off the case mouth. So I set it up to headspace off the shoulder like any other bottleneck cartridge.

As others have mentioned, make sure you get the correct bullets. I buy mine from Montana Gold. They make a special bullet for the Sig.

I size first in a carbide .40 S&W sizing die then run them through a steel 357 Sig die. This way I don't have to use case lube. I reduced the expander diameter so I am really not expanding at all. Just a light chamfer on the inside of the case necks and I don't have any trouble seating. The case neck is so short that you are asking for problems if you expand much. You just lose too much neck tension that you cannot recover with crimping. Setback needs to be checked and controlled. Some folks set the shoulder back more just to give more neck to grip the bullet.

Some good articles:

Real Guns article 1

Real Guns article 2

You can now buy a Wilson cartridge gauge from Dillon and that is a real help.

Pick the right powder. Most use AA #9 and that is what I use. Not a problem to load for, just some things you don't encounter with other cartridges.

jepp2 said:

This is generally what you will read, but that hasn't been the experience of most folks loading for the Sig. I load for 3 different Sigs and there is way too much variation in the throat length for it to headspace off the case mouth. So I set it up to headspace off the shoulder like any other bottleneck cartridge.

As others have mentioned, make sure you get the correct bullets. I buy mine from Montana Gold. They make a special bullet for the Sig.

I size first in a carbide .40 S&W sizing die then run them through a steel 357 Sig die. This way I don't have to use case lube. I reduced the expander diameter so I am really not expanding at all. Just a light chamfer on the inside of the case necks and I don't have any trouble seating. The case neck is so short that you are asking for problems if you expand much. You just lose too much neck tension that you cannot recover with crimping. Setback needs to be checked and controlled. Some folks set the shoulder back more just to give more neck to grip the bullet.

Some good articles:

Real Guns article 1

Real Guns article 2

You can now buy a Wilson cartridge gauge from Dillon and that is a real help.

Pick the right powder. Most use AA #9 and that is what I use. Not a problem to load for, just some things you don't encounter with other cartridges.

Click to expand...

All true. The headspace on the mouth myth is still being pushed even in todays manuals & anyone that reloads the 357sig knows that the shoulder is really the datum point for headspace. Too far forward & it won't chamber, too far to the rear & it will misfire, that is headspacing on the shoulder. SO setting up your dies for proper headspace is the first issue.
The next big thing w/ the 357sig is bullet selection. It will NOT run happily w/ any 9mm bullet. It requires a truncated cone shaped JHP or FMJ for bullets over 102gr. There may be some 115gr non TC profiles that will work loaded long, like in a 1911 paltofrm, but in most conventional 357sigs, 1.145"OAL is about as long as it goes & the bullet has to have enough straight bearing surface to provide good neck tension inside the a short neck. Get those two things correct & reloading the 357sig is no diff than any other straight wall case IMO.
I use the Dillon dies, the sizer is the only carbide one available. You can use a 40 carbide sizer, then size in a steel sizer to form the shoulder w/o any case lube. Either way will work. On dies, avoid the RCBS, they still have it wrong, a two die set, no expander & the die puts the shoulder in the wrong place. All others got it right, Dillon though wins on it's carbide sizer.

I was thinking off converting my HK or Sig 40 to 357 Sig.

The HK barrel is over $200. That along with reading those articles convinced me, why bother. Looks like a lot of hassle and expensive for no use to me. I'd rather use that money to buy a 10mm or something.

357 Sig is really easy. Just spend the money and get the carbide dies. I use a lee FCD on the sig and it helps also. With the right bullets (rem 115 JHP's are my favorite) and AA9 powder you are fine. You cannot cram enough aa9 to get in trouble and it supports the bullet so no setback issues.

I like the sig because it is so easy to reload.

Thanks for the feedback everyone, I really appreciate it. I think I have all the information I need to give this a try.

I had a very tough time reloading .357 sig. I could easily push the bullets into the case by pressing the cartridge on the bench edge. I improved (won't say "solved") the issue by not flaring the case mouth at all. (I use the special .357 sig 125g MT gold bullets). I seat the bullets very carefully. I crimp with the Lee FCD but the key here is NOT to crimp too much or you will lose neck tension. NECK TENSION holds the bullet, not the crimp. You cannot crimp your way out of insufficient neck tension. I really am still not comfortable reloading this round, but I have plenty of other calibers I work on.

Thanks Rodentman. I'm thinking I won't reload .357 Sig and your post confirms what I was thinking. I found I can buy reloads from Georgia Arms for only a couple of bucks more per 50 than it would cost to reload them so the financial incentive is gone. I've been reloading for a little over a year now and have learned a lot from this forum. I don't think I want to take this one on...like you I have lots of other calibers to reload.

I see that FredJ338 is on this forum as well. Fred is a frequent contributor to Sig Forum and is generally thought to be one of the reloading gurus there and for good reason. He has helped me through a number of issues. Good to see you here Fred !!!!!!

OCD1 said:

I was thinking off converting my HK or Sig 40 to 357 Sig.

The HK barrel is over $200. That along with reading those articles convinced me, why bother. Looks like a lot of hassle and expensive for no use to me. I'd rather use that money to buy a 10mm or something.

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Not really. An EFK bbl for my USP is how I started in the 357sig. I enjoy shooting the 357sig more in the ltwt USP than I do the 40.

Duvallmark said:

I see that FredJ338 is on this forum as well. Fred is a frequent contributor to Sig Forum and is generally thought to be one of the reloading gurus there and for good reason. He has helped me through a number of issues. Good to see you here Fred !!!!!!

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Thanks for the props. I don't know about guru, yes I do load for a couple dozen diff calibers & have been doing this longer than most, but I am still learning all the time. My introduciotn to the 357sig a few years ago is one example. I'll try to keep my image up here too. I used to come on & then got a new comp, etc, etc. Good bunch of guys here as well as the Sigfroum & I do love me some prelock S&W!

505Gibbs said:

Since the 357 Sig headspaces on the case mouth like the 45 ACP or the 9mm Parabellum etc. you need a good grip on the bullet. The original factory loads from Federal solved this by glueing the bullets in place[they and others may still do it today]!So . . you can't expand old cases too much or you'll not get enough grip and the only real 'crimp' would be a taper type. Using new cases with just a slight belling at the mouth of the case may resolve much of the grip issue - but I'll bet its trial and error.
Additionally, if you start loading 'hot' you'll have to be sure that rounds further down in the mag don't start having bullet setback and the subsequently higher pressures associated with this issue. I've based this just on my readings - I have all the cases and dies but I've never gone forward with it and just stuck with factory ammo.
We'll see how others respond on this. Just my $0.02!

Click to expand...

Any idea what glue or how they do or did this???

.357 Sig. I've heard it is more difficult to do but don't really understand why.

Click to expand...

The short answer is it's a bottleneck cartridge, for any reader who missed this point in the (very good!) details of loading a bottleneck pistol cartridge.

Straight-walled cases are just simpler to load and have fewer pitfalls to avoid. No shoulder setback, crooked necks, etc.

What class in USPSA do you shoot a 357 SIG?

shotslow said:

What class in USPSA do you shoot a 357 SIG?

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If you mean Division, it's legal in Open, Limited, and Limited 10. Class is awarded based on classifier scores.

It's not popular; if you're going to load those fat cartridges, why not use .40 S&W for Major power instead of Minor power for the .357? Nothing less than .40 can be major except in Open.

Maximumbob54 said:

Any idea what glue or how they do or did this???

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Bob - I called Sierra and they had no idea nor have I been successful locating it anywhere else. Many of the military match loads used a glue at the neck for sealing and retention.

I've posted to the article and read the current updates and my question to those that state that it headspaces off the shoulder - IF it does[and you may be all correct in saying it] then why didn't they use a bullet with a cannelure?? This is no big deal for a mass loader such as Federal but nobody does to this day.

505Gibbs said:

Bob - I called Sierra and they had no idea nor have I been successful locating it anywhere else. Many of the military match loads used a glue at the neck for sealing and retention.

I've posted to the article and read the current updates and my question to those that state that it headspaces off the shoulder - IF it does[and you may be all correct in saying it] then why didn't they use a bullet with a cannelure?? This is no big deal for a mass loader such as Federal but nobody does to this day.

Click to expand...

You could, it's been done. The issue is most bullets suitable for the 357sig do not have one & most dies are setup as taper crimp.

I've loaded somewhere around 13,000 rounds of 357 Sig ammunition so far. I've found that there are actually two datum points for this cartridge, the case mouth and the shoulder. This was discovered the hard way when a too thick shell holder wouldn't allow the case to be driven far enough into either my Redding or Dillon 357 Sig dies to set the shoulder back enough for the rounds to chamber. I simply milled off a few thousandths from one of my shell holders and dedicated it to loading this caliber. I've also come across some Federal nickel cases that were too long and had to be trimmed to make work. That's the only pistol brass I've ever had to trim, and I've loaded somewhere around 750,000 rounds of ammunition in 31 calibers since 1963.

I haven't read through all the posts in this thread, so this may have been covered, but chamfering the inside of the case mouth greatly helps with bullet seating. It only has to be done once, but it helps quite a bit. I also add a cannelure to any bullet I'm going to use for the 357 Sig, including Berry's 115 and 124 grain Flat Point 9mm bullets, which shoot very accurately if kept to below 1,300 fps. They will tumble at roughly 1,450 fps and hit the left support for the shade on your chronograph...... But that was with a healthy dose of Power Pistol. I use the Dillon 357 Sig crimping die for the crimp.

My standard powder for 357 Sig is Accurate #9. It fills the case and helps prevent bullet setback and is very, very accurate out of both of my 357 Sig pistols, a Springfield XD and a Witness. The XD shoots best with the 124 gr. bullets and the Witness shoots best with the 115 gr. bullets, just proving once again that all pistols are individuals.

I've found that there is no mystery with this caliber and that it's fun to shoot. Little recoil, loud and flat shooting. Hitting clay birds on the impact berm at 50 yards is no problem with either of my pistols in this caliber.

It's probably been mentioned, but bullet selection is critical with the short neck and magazines. Any NATO profile bullet is going to fail if loaded in 357 Sig. The ogive will be inside the case neck and there won't be any neck tension to hold it in place. As mentioned, I like the Berry's, the Speer Gold Dot 357 Sig bullet and Hornady XTP's. They all load well and shoot well, which is all I can expect from a bullet. I don't worry about expansion, since paper isn't going to expand any bullet, and for carry use, Speer loads their 124 gr. Gold Dot for that.

Sorry if I duplicated anything already covered, but like I said, I didn't read through all the posts.

Hope this helps.

Fred