Self-Defense: .357 SIG And .357 Magnum Ammo Considerations

From the right gun, most .357 SIG and .357 Magnum ammo choices are the best and hardest-hitting self-defense rounds.

Pros and cons of the .357 Magnum and .357 SIG:

Pros:

• Exceed FBI test standards for penetration.
• Able to defeat the most common barriers.
• Excellent performance no matter the bullet weight.
• .357 Magnum has among the best reputations as a stopper.
• .357 Magnum can also shoot .38 Special.

Cons:

• Both cartridges require barrel length to achieve desired performance.
• Given barrel considerations, carry options aren't a fit for every armed citizen.
• Excessive muzzle blast.
• Recoil with full-powered loads can be excessive.

The .357s are the start of the revolver cartridges that have enough horsepower to easily pass the FBI tests. This is both good and bad. It’s good in that you can count on any of the modern bullet designs to get the job done. No new bullet, in either .357 Magnum or .357 Sig, will fail the tests. They will all, in any weight (the .357 Sig doesn’t offer many choices there, but that’s not a big deal) penetrate well past the minimum depth, expand, and do so even after passing through barriers.

No, the problem is blast and recoil.

A .357 Magnum load in particular was the focus of stopping power inquiry a few decades ago. The 125-grain JHP was seen, even by those who were not fans of the “smaller” calibers, as having a sterling reputation as a stopper. As well it should have. The projected velocity of the 125 JHP was 1,450 fps. That was not the real velocity, of course, but that was what everyone used as their goal, their aspirational speed, if you will.

It came close out of a 6-inch barrel, doing high 1,300s, but out of the more-common carry gun it was between 1,250 and 1,300 fps. Which was plenty to get the job done.

Where in the 9mm the research was to produce a bullet that would expand at the velocities that could be generated, in the .357 the task was to design a bullet that would hold together at the velocities already existing.

.357 Sig

The Sig was designed to deliver the ballistics of the .357 Magnum out of an autoloading pistol. The case is essentially (but not as a practical, handloading matter) the .40 S&W necked down to 9mm. It has a capacity close to that of the .357 Magnum, and therefore can generate the same velocities as the longer revolver cartridge.

But, and this is important to understand, it is limited in the same way the .357 Magnum is: it needs barrel length to deliver. If you expect to get the full .357 Sig ballistics out of a 4-inch barrel, you are kidding yourself. If you go for a compact .357 Sig, you are basically doing the 9mm+P+ dance, but only with more noise and blast.

More .357 Magnum Articles:

• The Advantage Of The .357 Rifle
• The .357 Magnum: 20th Century Handgun and Cartridge
• Classic Guns: The Smith & Wesson .357 Magnum Revolver

So, if you want the full .357 Sig power, you have to be willing to pack a full-sized handgun. If you are not willing to pack the biggest one, then save yourself the hassle and step back to a 9mm, since that is about all the velocity you will be getting anyway.

.357 Magnum and .38s

One of the big advantages of the .357 Magnum is that revolvers chambered in it can also readily fire .38 Special ammunition. This is good, as it allows for less-strenuous practice. This is bad if you use .38s for practice and then load up with full-power .357 Magnum ammo for EDC. This was supposedly one of the problems encountered in the Newhall incident. At the time, the California Highway patrol and many other law enforcement agencies felt it entirely appropriate to practice with .38s (sometimes even soft-recoiling .38 wadcutter ammo) and then carry .357s on duty.

One problem is that the shorter .38 cases cause lead and powder residue buildup in the chambers. The bigger problem is that the practice isn’t similar enough to be useful.

If you want to use .38s in a .357 because you don’t want the recoil, and want a stronger, longer-lasting revolver, go right ahead. Just don’t think that practicing with .38 is going to fully prepare you to use your revolve when loaded with .357 Magnum ammo.

Light bullets

The lightest carry revolvers often have a warning to not use the lightest bullets. This is for good reason: the bullets will “jump the crimp” due to inertia and recoil. While it is rare for a round to pull longer (the revolver moves back, the bullet “attempts” to stay in place) enough that it will tie up a revolver in only four or five shots, you should not risk it.

If you want to test, fair warning: the recoil is beyond stout, it is sharp enough to be painful, and you can easily work yourself into a flinch. In fact, you probably shouldn’t use full-power .357 Magnum ammo in the lightest-available carry revolvers. It’s just no fun and you can’t really practice, just learn what your pain threshold is.

Choosing ammo

The problem is not picking what works, they all work. The problem is in picking something you can live with. In addition to the advice with other calibers (use what is reliable, use what is accurate), you can add use what you can stand to shoot.

In a certain sense, you could call me a professional shooter. I shoot more ammo on an annual basis than most people walk by at the big-box store when they go to buy ammo for a day at the range. I have shot, and continue to shoot, every handgun caliber made. Several times a week I’m at the range, and several times a year I spend a week at a class, range, seminar or other industry function. I shoot a lot.

I don’t find any full-power .357 Magnum ammo to be fun in any revolver below the medium-frame all-steel ones. One of my favorites is an old S&W M-65, 3-inch, in .357. That I’ll shoot a lot, but not all day. If I’m shooting all day with .357s, then they go through the M-27. The lightweights? Unless it is for an article or a test, I will only put .38s, and not a lot of .38+Ps, through them. It’s just no fun, it’s too painful and I don’t want to learn a flinch.

This will take some work and range time. That’s good, because there is no such thing as too much, and certainly there is such a thing as too little. The bad news is that this may be work, could be annoyingly painful and will take time.

Now, in the .357 Sig I have one top choice, and that is the Hornady Critical Duty. Of course, I’ll only pack it in a full-sized pistol, but boy, what performance you get.

Ammo performance chart:

* Bare gelatin for penetration and expansion, unless otherwise indicated
** 4” barrel
*** 6” barrel

Editor's Notes: This article is an excerpt from Choosing Handgun Ammo: The Facts That Matter Most for Self-Defense by Patrick Sweeney.

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