.357 Sig

Just curious - this was supposed to be a screamer, to achieve .357 velocities out of a 4" pistol barrel. It’s pretty much a dead caliber, now.
Any experiences - pro or con - with it?

Some info on this thread… It’s pretty short though: .357 Sig


That is like saying 10mm is dead. Just depends on where you live.

I would love to get back into it, but I can’t decide on what gun to get. I have been trying to find a Glock 30 at a reasonable price, but not finding one. I have seen some barrels done for a Beretta 96 too. With the current ammo situation, I am not inclined to even think about it right at the moment anyway.

The round is zippy, but from what I remember you really have to get a boutique load, or your own, to get the best of it. I think the Sig loads might be where they should be. There is more blast/recoil than a 9mm, but not quite like a .40 snap is.

10mm seems to be coming back especially in 1911s

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No direct experience with it, but ammo was on sale at PSA recently :smiley:

If memory serves, the 357 Sig was supposed to use 9mm bullets out of a larger case (.40S&W ??) to serve a sort of middle ground. IE stronger than 9mm, but less recoil than .40S&W. It was targeted at LEO but just never stuck. I don’t think it’s because it’s a bad round, I just think modern 9mm effectiveness increased to the point where you didn’t really need that intermediate cartridge.

I seem to recall that if you get just the right firearm model, you can shoot one caliber larger (.40?) and one caliber smaller (9mm) in addition to the 357 Sig.

Because it was targeted to LEO and it got some traction there, there was a good while maybe 5-10years ago (or more?) where you could get a lot of police trade-ins for a good price as those contracts ended and they moved to a different caliber.

.357sig uses a .40 case neck down to 9mm. Typical load is a 125gr bullet duplicating the .357 load. The round is still used by agencies, typically out west. Here in Montana it is still in use by the Highway Patrol.

Finding a barrel to convert a .40 to .357sig is a common way to get it if you already have .40. To my knowledge you can new guns from Glock and Sig. I have seen conversion barrels for Beretta, CZ, S&W, Sig, and Glock.

If you want to reload, you need to get a bullet that was developed for it. With the case neck, it just has tension on that part of the case. So, bullets for .357sig will be made to get you more purchase there. A very popular one is from Montana Gold Bullet.

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I’ve shot this caliber from guns designed for this caliber and converted .40 caliber.

Personally, I think it’s a great self defense round. Terminal ballistics are good and it’s noisy from the bullet going supersonic (noisier than most other rounds I’ve shot - even other supersonic). The noise creates a psychological advantage in some cases because people wonder what someone is shooting at them. (The same is true of the .50ae but without the weight and price tag associated with .50ae.).

The caliber is less common and carries a slight price increase over more common calibers but that’s negligible currently. The ammo for .357sig was available for longer than 9mm when supplies started to go low. But this is true for most of the less common caliber options.

Recoil is quite manageable for most people.

You can swap barrels and shoot .40 caliber ammo as well which can pull down the cost for range time and drills. Keep in mind that there is no other change needed to shoot .40 or .357sig from the same gun. Magazines, case geometry for the extractor, everything else is the same.

But the ballistics can be mimicked with some 9mm+P so there isn’t necessarily a reason to buy over other options if that’s your only concern.