Please Educate Me On This

[Single Six]

I already have a great 9mm pistol [Ruger P-95], which I can load up with 9mm +P+ JHPs for defense. In your opinion then, what, if any, advantage would be gained by my buying a pistol chambered in .357 Sig? The 9mm +P+ seem to be quite close [in terms of ballistics] to this round. Am I correct on this, or am I missing something? Thanks, all.

 

[farmerboy]

Well you could have a harder time finding ammo and when you do pay a quite abit more for it. Other than that I don't see any more advantages. Wait, those ain't even advantages, are they? No advantages

 

[carguychris]

The main advantage of .357Sig over 9mm+P+ is that you're not using an overpressure round loaded in excess of SAAMI specs. Gunmakers will stand behind the warranty of a pistol chambered in .357Sig but not necessarily for a 9mm pistol that is damaged while shooting 9mm+P+.

There are precious few pistols for which the use of +P+ is officially endorsed by the manufacturer, and AFAIK the P95 is not one of them. FWIW pistols with official +P+ endorsements- or an unofficial reputation for easily withstanding long-term use- are usually platforms designed around .40S&W but also offered in a 9mm version. "Indestructible Ruger" mythology notwithstanding, the P95 is not offered in a .40 version, and the fact that it uses a completely polymer frame without metal inserts does not bode well IMHO. YMMV.

 

[TunnelRat]

I'll bite.

I don't like +p+ ammo. To me if you feel like your caliber of choice is only effective in +p+ then you should really use a different caliber, as you don't seem to have a lot of confidence in it. I also don't like the fact that it doesn't have a true SAAMI spec. Not too many manufacturers recommend its use, and even then you're putting more wear and tear on the gun. It's also often a good deal different recoil wise than what you might practice with. To me you should practice with a loading similar to what you would use in self defense. That to me is one benefit of 40 SW and 357 SIG, the defense loadings are often very similar to the practice ammo.

In short I like 357 SIG because I'm shooting +p+ 9mm out of a barrel designed specifically for that. As always, YMMV.

Edit: Chris, beat me to it once again.

 

[carguychris]

FWIW numerous .40S&W / .357Sig pistols can be outfitted with 9mm conversion barrels for lower-recoil, low-cost practice and plinking. This is another check mark in the .357Sig's favor.

 

[Single Six]

Carguychris: I think that you might well have just rendered any further replies unnecessary. Thanks for that explanation [you too, TunnelRat]. I guess maybe I do need to look at getting a .357 Sig. Thanks!

 

[KyJim]

I've never seen the need to go beyond +P in 9mm. If you want additional umph, maybe a 10mm. There's better variety of ammo and loads in that caliber than .357 Sig.

 

[farmerboy]

Why do you think you might need +P+? You think you might shoot someone with your 9 and they won't go down? I think not. Your 9 is fine just how it is and also a plus is the cheaper ammo, lighter recoil, easier ammo to be found, etc, etc.

 

[bamaranger]

no crime

There is no harm in wanting more performance from your handgun.

The comments on ammo availability and cost are valid. The .357Sig MAY feed better due to its bottleneck shape, but that is likely conjecture.

I would not shoot a steady diet of +p+, but for carry, why not?

I have never been a real fan of the .357 Sig. And if we're going to campare it to hot 9mm, what about .38Super +P?

 

[MLeake]

While there are pros to the .357 Sig, there are more downsides to it than just cost. The same downsides apply to 9mm +P+, essentially:

Muzzle blast;
Muzzle flash (especially at night);
Slower follow-up shot capability.

I am happy with 147gr HST standard pressure in most of my 9mm pistols, and 124gr +P HST in the one gun that does not feed 147. Tests indicate very good performance with either.

Edit: I had a P229 with .40 and .357 barrels. It was much louder, much flashier, and much flippier than similar pistols in 9mm.

 

[carguychris]

And if we're going to campare it to hot 9mm, what about .38Super +P?

All .38 Super ammo is designated +P by SAAMI. IOW new ammo labeled .38 Super+P nominally isn't any different than older ammo labeled simply as .38 Super (or Super .38).

This somewhat confusing terminology is meant to differentiate this cartridge from .38ACP, which uses the same case and bullet, but is loaded to lower pressure- at least officially. (Some historians argue that original .38ACP military ammo was loaded very close to modern .38 Super, but this is a sidetrack.)

.38 Super has very similar ME to .357Sig but it's typically loaded with slightly heavier bullets. However, it uses a semi-rimmed rather than rimless case, so it feeds more reliably from a single-stack mag than a double-stack one. It's also somewhat long. Consequently, it has historically been used mostly in the M1911 platform. OTOH the ability to use a double-stack mag in a pistol with small 9mm-ish grip dimensions is the main selling point of .357Sig (and .40S&W).

 

[Cheapshooter]

Here we go again. Somebody with a 9MM that wants to turn it into a more powerful gun by using over pressure ammunition. This seems to come up almost weekly. If you do not have confidence in any of the modern 9MM rounds suitable for your guns capabilities, get something else. But will more power make you shoot any more accurately'
carguychris, TunnelRat, KyJim, farmboy, Mleake have all given you the best advise, and information you could have. As far as the 357 Sig goes make a simple observation. Look around and see how easy or hard it is to find ammunition. Also compare costs with rounds more powerful than 9MM if that is what you want. what ever you have for SD/HD it is important to shoot it often in order to be proficient in it's operation, and accurate in shooting. A well placed 9MM standard pressure SD round will be much more effective than a lot of poorly placed +P+, ++P++, or as many pluses as you want to add.

 

[sailskidrive]

9mm has been dropping two legged creatures just fine for nearly 100 years; I really don't see the point in +P+.

A ER/OR physicians perspective on gunshot wounds:

http://www.youtube.com/watch?v=tku8YI68-JA

 

[RickB]

If I'm getting only .40 mag capacity, I want .40" bullets.

 

[drail]

+P+ 9mm is for people who can't or won't trade up to a more serious handgun. ( I'm just funnin' ya)

 

[Single Six]

Drail: I agree. That's why my normal SD/HD piece is a .45. However, I use the P-95 strictly for monthly training due to 9mm ammo being cheaper. It just occurred to me that if I should decide to use it for serious stuff, I'd give the +P+ a try.

 

[TunnelRat]

It just occurred to me that if I should decide to use it for serious stuff, I'd give the +P+ a try.

I can think of a number of standard pressure 147 gr loadings and +p 124 gr loadings that I consider "serious" enough.

 

[drail]

+P+ loads will shorten the life of your gun if that matters to you at all. And honestly, if you can place the shot precisely a standard 9mm will do the job just fine.

 

[orionengnr]

Here we go again. Somebody with a 9MM that wants to turn it into a more powerful gun by using over pressure ammunition.

You are overlooking one obvious reason for using +p or +p+.

A shorter barrel gives up velocity, and thereby sacrifices some performance.
But shorter barrels are very handy for concealed carry pistols.

Using +p or +p+ in a short-barreled pistol (like my PM9, or my P45, or my 3" 1911) regains a good bit of that lost velocity and recaptures much of the otherwise-lost performance.

Yes, I realize that it will increase wear, probably to a negliible degree, given the number of rounds involved. Since I can't afford to burn thousands upon thousands of +p/+p+ rounds per year, it is basically moot. And if I could afford the ammo, I could also afford to replace the gun from time to time.

I own several different carry pistols, and shoot them regularly with range ammo. And if I send a mag or two of the hot stuff downrange every now and then...it is not the end of the world, for the gun or for my budget.

Until someone can convince me that I am seriously misunderstanding or miscalculating this equation, I will continue to follow this practice.

 

[MLeake]

Heavier rounds, such as HST 147, use longer bullets, which leaves less case capacity. The plusses are that pressure is achieved with less powder (due to pressure having an inverse ratio to case volume); the heavier bullet remains in the barrel longer (due to greater mass having more inertia and less acceleration); because of the previous two factors, a higher percentage of powder is burned while the bullet is in the barrel; because of that, the heavier round actually loses a lower percentage of its velocity out of a short barrel than does a lighter, faster round.

Many +P rounds have diminishing returns from short barrels as much of the powder is burned after the bullet has left the barrel. More velocity loss is induced, and more flash and bang are produced.