Sig 357 vs ,357 s&w

[Bart Noir]

Thinking of adding a 357 sig
to upgrade
My m66 s&,w.

So I thought the OP wanted to bore out the M66 chambers to take .357 SIG cartridges. Boy was I dumb!

Hey. Wait a minute.

Why is that a bad idea? Well, I think it would take a new cylinder rather than a re-bore of a .357 Magnum cylinder. But a 6- or 7- shot revolver in .357 SIG might be interesting. Quick reloads with full-moon clips.

Bart Noir

 

[J.G. Terry]

How I got there....357 SIG

This is my experience: Some years back I had a 229 SIG with 357 SIG OEM barrel. At that time I learned how to load cartridges. Sold that gun regrettably. Later came up with a Glock G23 Gen5. Later a factory drop in barrel in 357 SIG was added. This arrangement has worked flawlessly with handloads or factory cartridges. Accurate and powerful. There are only four S&W 357's on hand here. Some folks can conceal a Smith 28-2. I not one of them. My 19 has a 6" barrel etc. Actually, I'm revolver poor counting Ruger Revolvers. Point here is that I can get a compact self-loading pistol that will work as a carry gun with only fourteen rounds. To me we are talking about two different worlds. Given a choice it would be for me with a Sketer Skelton 44 Special loads in my 624 Smith. This would be with my hand cast hollow points etc. This is not a choice so its the G23 with factory 357 SIG barrel. Sorry, no aftermarket stuff in my carry gun.YMMV Those Smiths are not for-sale as long as I'm on the green side of the grass.

 

[dgludwig]

As a side note, on occasion I've read that the bottle-necked configuration of the case adds to the reliability of the feed from magazine to chamber. May just be a theoretical advantage; I have no experience with the cartridge myself.
I have, however, always been intrigued with the idea of a semi-auto replicating what many feel is the "gold standard" of "stopping" power for a self-defense round: the .357 Magnum with a 125 grain HP bullet.

 

[Jazzgun]

Have you considered a S&W 360 357/38 +P that shoots both calibers? That's the gun on my night stand. It helps me sleep better. It's my serious, snub nosed scary looking gun. No pink grips or anything fancy. Just business!

oops! I think I didn't realize this wasn't in the revolver section. Sorry bout that. Moderator can delete my post. No problem.

 

[Buckeye!]

I like my Glock 32 ..... and Underwood rolls'em right !!!!

 

[trooper3385]

The 357 sig has nearly identical ballistics to the 357 mag using 125 gr bullets. The advantage for the magnum is being able to use heavier bullets. The sig was designed for the 125 gr and that’s pretty much what your limited to. I’ve carried a sig 357 sig for 17 yrs. A Sig P226, P226 DAK, P229 DAK, and a P239 DAK. I have also carried the Glock 32 and 33 for other than issued. In my opinion, it’s the best caliber on the market for L.E. I can count the number of jams I’ve had with any of the listed guns on one hand. One thing I can say about my agency is they don’t spare any expense when it comes to training and training ammo. I’ve fired 1000 plus rounds a day and several occasions. I have all of those guns listed in my safe now and the barrels still look good and shoot just as accurate as the first day I got them new and they all have probably 10,000 rounds on them. Well maybe not the P239 and the glocks. I’ve never heard of a barrel being shot out after 3000 rounds. The reason they are in the safe now is we just (yesterday) switched to the Sig P320 in the 9mm. I have to say after 500 rounds yesterday and another 500 rounds today in 2 P320’s I was issued, I was thoroughly impressed with it. Although 9mm would not have been my first choice. Supposedly, according to our training section, the 9mm with the 135 gr Hornady critical duty performs almost as good as the 357 sig although I would like to see that to believe it.
On a side note, my agency tried to switch to the S&W M&P 9mm a couple years ago. The gun didn’t even last through a full recruit school before they decided to pull it and re-issue the P226 to the recruits. You can imagine how big an issue this created when they already had 5000 plus guns, duty gear, and ammo in stock for the whole agency that they had to return and how big of an issue they had with the S&W’s to come up with that decision. They had multiple problems with the S&W’s that could not be corrected. Our local police dept uses the S&W in 40 cal and they said they have not had any problems, so maybe it was just an issue with the 9mm’s and may have since been corrected. Not sure.

 

[dgludwig]

The sig was designed for the 125 gr and that’s pretty much what your limited to.

A couple of posters in this thread have noted that you can get 147 and 180 grain bullets for the .357 SIG. I haven't seen any on the shelves myself and I wonder how many factories made ammunition using bullets heavier than 125 grains for the .357 SIG?

 

[Swamp Yankee]

Roll your own,

To my limited knowledge, other than Sellier & Bellot who loads 357 Sig in140 grain FMJ flat nose the commercial loadings I've seen are 125 gr.

Loading your own opens up possibilities to weights up to 147 grain in multiple bullet configurations. I've had excellent results with MG 147 gr CMJ and Speer 147 gr Gold Dot and TMJ. No issues making Major with any of those three. In a YMMV situation, I've found the 147 gr seem to feed better than the 125 gr in my 357 Sig chambered 1911.

Not familiar with any 180 gr bullets that are acceptable for 357 Sig but if they exist, could someone post a link.

Without get getting into a leg lifting contest, my own opinion is the 357 Sig marketing around the 125 gr load, fails to accentuate the benefits obtained with loads using 130 to 147 gr.

It's a fun cartridge if you want to play with it, but unless you load probably not everybody's cup of tea.

Take Care

 

[Buckeye!]

I have been a 357 Mag fellow for years ..But I have over the last few years , been leaning toward semiautos.. Mostly (99%) Glocks ... And one of my favorite carry pistols is a 32 (23)
with a 357 Sig barrel , that is ..
As tbe 357 Mag with 125gr JHP is known as a "stopper". The 357 Sig is in all practical purposes equal in that respect.... And with Underwood 125gr Gold Dot out of a 32 makes a formable SD round

https://youtu.be/ughIFOrIP_w

 

[Oldjarhead]

The 357sig 125grain hollowpoint in the Speer gold dot hollowpoint hums in at 1350 fps, which is slightly below .357 magnum levels. Still a very good, and proven round. I know personally from Texas DPS (highway patrol) and Texas Rangers have carried that round in their Sig Sauer p226 and p229. They have since gone back to 9mm, but I don't know exactly why. I own and carry a Sig Sauer P229 SAS gen 2, with a .357sig barrel. Shoots great. Sigs, and. 357sig ammo are both expensive. Depends on how much you want to spend.

 

[cje1980]

My experience is that the 357 Sig is comparable to service grade loads for the 357 Magnum. Not the hot original hot loadings or the hottest stuff out there today. Out of a 4" barrel 125 gr loads will do about 1375-1400+ fps which is comparable to service grade 125 gr 357 loads. It's a bit of a myth that the 357 Sig is only comparable in the 125 gr loads. I used to have a Glock 31 with a 4.5" barrel and factory Hornady 147gr XTPs ran 1250 fps. That's right on par with the classic 145 gr silvertip 357 load. A lot of people diss the 357 Sig as simply being a hot 9 but that's just pure bologna. I used to use the 357 Sig in IDPA and I deliberately tried to download to 9mm levels. Even starting loads were well above +p 9mm velocities. I was running Berry's 124 gr FN bullets with starting charges of longshot and was getting 1300 fps. The 357 Sig is a legit round.

 

[cje1980]

Oldjarhead, there are two Speer 357 Sig Gold Dot loads. They are loaded to different velocities and actually have different bullet designs. One is loaded hotter and doesn't expand as robustly and is designed to penetrate barriers better. The other is loaded to 1350 fps and expands more robustly and doesn't penetrate as much. I used to keep my Glock loaded with Federal 125 gr HST and they ran about 1400 fps out of the Glock 31 and they were designed to expand robustly. I think that load mimics the classic 357 Mag 125 gr SJHP loadings pretty well.

 

[cje1980]

JeffK, I find that really hard to believe. A pistol round wearing out a barrel in 3000 rounds. 308 and 30-06 barrels last longer than that and we are talking about projectiles going 2700+ fps. 5.56 barrels last longer than that launching projectiles 3000+ fps.

 

[EnoughGUN]

I don’t think you can go wrong with either. Are they both more expensive than 9mm sure. Are they both better performers? Depends on how well you shoot them. And that is highly subjective.
They both will pack more punch than some lesser rounds but if you can’t handle the power of a v8 buy a 6 cylinder right?
I’d say go 357mag if you want a revolver and sig if you want a semiauto. Either comes with a premium so make the investment and if you go sig buy a 9mm barrel and mag (if it’s a 229) to practice with.
I love 357sig and carry/ shoot a couple guns chambered in it including a usp compact and a 229 legion. I honestly don’t see any big issue with the power of the 357 sig. it doesn’t seem appreciably more violent than anything else. Matter of fact my usual range toy is an EAA witness limited in 9mm and I shoot the legion almost if not as good as the Witness, high bore axis BS and all.
All factors of modern firearms and ammunition considered I think the only thing you are gaining with either of these is probably barrier penetration, possibly sightly larger cavity, better expansion and better penetration through heavier clothing..... now that I write that it seems like a lot of advantages lol. I carry the extreme defender rounds which are solid non expanding light high velocity rounds. They knock some weight off the rig, lessen the recoil and help take expansion issues out of the equation.

The more I think about this subject and discuss it with people the more I think that the difference in most of these calibers is negligible. Everyone looks for the magic bullet but it’s like comparing several cars all producing within 10hp of each other. I hate to be the guy that throws out all the cliches but the best gun is what you actually carry that you can hit with and holds the most bullets.

 

[cje1980]

I agree with the above. I actually shot IDPA with 357 Sig for a while. It's loud but doesn't really have a violent recoil impulse. I found much more pleasant to shoot than 40S&W. I always found it very accurately and it would hit poppers with more authority than the 9mm. Some of the other competitors out there were impressed with the authority it hit steel. I think the best load for carry/HD is the Federal 125 gr HST loading. It's not downloaded like some of the other stuff and it expands violently while still meeting all the FBI protocols. I disagree with some folks that say it lacks versatility. There are many loads out there for the 357 Sig that accomplish many different tasks. The Hornady 147 gr XTP is a nice outdoors load with a controlled expansion projectile, nice sectional density and more velocity than 124 gr +P 9mm loads. There are some heavier loads out there as well. Speer also has a couple of loadings in their Gold Dot line. One is loaded hotter (54234) and is more of a controlled expansion projectile while the other (53918) is loaded to a slower velocity and meant for more expansion.

 

[SDF880]

I took 2 M&P40c's and put aftermarket 357SIG SS barrels in them and they have been my EDC for several months. Some really hot 357SIG rounds out there now!

 

[Sgt127]

I bought a Sig P239 in .40. Found a 357 Sig barrel and mags. I’ve yet to switch it back to .40. The 357 Sig is an awesome round. It will out preform any +P+ 9mm. With a lot less wear and tear on the gun.

That said, I often carry another P239 in 9mm.

 

[cje1980]

Sgt127. I don't understand why think the 357 Sig creates less wear and tear than the 9mm. The 357 Sig is going to have more slide velocity and runs at 40K psi as opposed to 38.5K PSI for the 9mm +p.

 

[Sgt127]

In the Sig P239 the slide is heavier and, the recoil spring is stronger in the .40/357 SIG version. It was designed for a hotter round.

 

[Jwilson904]

Sig or HK