9mm+P+ vs. .357 Magnum

I'm not a Veteran or an LEO,never shot at or been shot at by a human,etc.

I do not claim much .

I have been told by someone with expertise that its about frontal area and penetration(assuming,of course,you get a hit).

Adequate penetration.Penetration through the bad guy,the wall,and down the block is not helpful.

Once you have adequate penetration,trauma is related to frontal area of the projectile.

In the two loads described,initially,frontal area is essentially identical.

Velocities are close enough that its unlikely one will give adequate penetration while the other will not...solely based on velocity

IMO,at this point,given the OP compared these two loads,it is apples and apples and the difference is insignificant,relative to the OP's question.

However,the bullet performance will make a difference.A loose,violent expanding bullet will up the frontal area at the expense of penetration.

Bullet performance will answer the OP's question better than anything else

Platforms?I used to have a MAB P-15 double stack 9 mm with a rotary lock that was designed to use submachine gun ammo.I wish I still had it.

It would be fine,I think.

Not every airweight compact .357 will hold up real well to full house .357 loads,either.

It is also true,once a loose expanding bullet opens up,it may lose most of its velocity in 2 or 3 inches,while a little harder bullet will maintain a higher velocity deeper into the target.

I think there are enough variables there is no simple answer.
 
I find that amusing for two reasons.

First is that the 9mm NATO round is by SAAMI / CIP definition a +P round. CIP places the max pressure for the 9mm at 34k PSI NATO is 36,500 PSI measure by CIP method.
Click to expand...

Actually it's pretty typical legal speak that is found in pretty much every manufacturers manual.

Here's Smith's clause from the M&P manual (after several paragraphs on ammo warnings, note how they even put the quotes around +P and +P+). I do find it amusing how they mention revolvers and this is the manual specifically for the M&P.

" “Plus-P” (+P) ammunition generates pressures in excess of the
pressures associated with standard ammunition. Such pressures
may affect the wear characteristics or exceed the margin of safety
built into some revolvers and could therefore be DANGEROUS. ...

“Plus-P-Plus (+P+) ammunition must not be used in Smith &
Wesson firearms. This marking on the ammunition designates
that it exceeds established industry standards, but the designation
does not represent defined pressure limits ... "

source: Smith & Wesson Instruction and Safety Manual for M&P Pistols

Check the manual for your gun, I bet a similar clause is in there as well.


The biggest problem here I think is using a wiki for a source. +P Does Not Equal NATO and hence the false discrepancy. NATO ammo is ok as it has a specified pressure rating (note the Beretta manual did not exclude NATO ammo). +P does not have a rating, it simply means over pressure and since it has no specified limit, it is impossible to say it is ok in any gun (although your wiki's will try to give it a range, it has none.) +P+ is more or less a joke in that over pressure is overpressure and since +P really has no upper limit, then what the heck is +P+? It's really just trying to say way over limit but you will note some '+P' offerings are just as hot or hotter than the '+P+' ones.
 
back in her day the .357 was the number one man stopper on the street holding a high casualty rate to go with it I read this years ago in a study based on all calibers the were used at the time, cant find it any more but again that was then and not now I am sure the statistic is based on the life of the cartridge while in service. longer service life better stats I have both like them and each one has her purpose if you are that troubled on the two then get them both and let it be over with :D
 
If I were a diehard .357 fan looking to switch to an auto, I'd simply buy my favorite auto chambered in .40 S&W. The ballistics aren't exact, but close enough. If I absolutely had to get closer, I'd go with 10mm. .40 is easy to find and relatively cheap. I'm lazy.....
 
+P does not have a rating, it simply means over pressure and since it has no specified limit, it is impossible to say it is ok in any gun (although your wiki's will try to give it a range, it has none.)
Click to expand...

This is incorrect. While CIP does not recognize a +P designation in any caliber, SAAMI does recognize such a designation for .38 Special, 9x19, and .45 ACP and the designation means that the cartridge in question is loaded up to 9-10% higher pressure than maximum standard pressure (.38 Special is 18,500psi or 9% over standard, .45 ACP is 23,000psi or 9.5% over standard, and 9x19 is 38,500psi or 10% over standard). Also, most SAAMI member companies label their .38 Super Auto ammunition as +P even though it is loaded to standard pressure in order to discourage its use in a gun chambered for the lower pressure, but dimensionally identical, .38 ACP cartridge.

+P+ has no defined pressure limit and is whatever the manufacturer deems fit. +P+ ammo that is made specifically for handguns by reputable companies like Winchester, Remington, Federal, and Speer is usually loaded to about 20% over maximum standard pressure (Winchester actually provides the max pressure of their +P+ ammo on their website).

http://winchesterle.com/Lists%2FCatalogAmmo%2FAttachments%2F8%2FRA9115HP.pdf

http://winchesterle.com/Lists%2FCatalogAmmo%2FAttachments%2F13%2FRA9TA.pdf

Military surplus ammo or that made by small boutique ammo makers which is labeled as +P+ or +P in any cartridge other than .38 Special, .38 Super Auto, 9x19, or .45 ACP may be loaded to much higher pressure.
 
+P, +P+

Ok, my mistake on the +P ... sort of. It is a recognized SAAMI marking however it does not indicate (per SAAMI) an actual pressure. Just that it is over the maximum allowed for SAAMI standard pressures but not by more than 10%. However, since the standard SAAMI pressure is a maximum rating and ammunition will be something under that (and vary by type and brand), the actual amount a +P cartridge will be over a non +P cartridge still falls into the ??? bin. Using 9mm for an example, All you really know is non +P will be under 35000 PSI and +P should be between 35000 and 38500psi. It still leaves this undefined vagueness to it (it's hotter, but you don't know how much hotter) which is why the disclaimer in the owners manuals (note: they don't say it will void your warranty either, they just don't recommend using it). By contrast, 9mm NATO has a defined pressure rating (of 36500psi I believe) placing it in a specific spot about half way up the +p ladder. And as stated, the +P+ is not recognized at all, so although it is supposed to be a pressure higher than +P, +P+ has no official meaning so anything over the SAAMI standard limit could be stamped +P+. You have to read the specs, the marking itself really means nothing (you want it to mean more than 10% over standard SAAMI, but it just doesn't mean that.)
 
After multiple hits of 9mm Platt still fought on. One of the findings after the shootout by the FBI was the 9mm Winchester round did not penetrate enough.
Click to expand...

Waitasec.

The 9mm Winchester in question was fired at a guy shooting a rifle (Ruger Mini-14). It hit him in or near the left hand, went through his whole forearm, then most of his bicep, crossed a short air gap into his chest, penetrated another 4+ inches and stopped barely short of the goblin's heart, fully expanded. It did serious damage along the way including cutting the main arm artery at the inside bicep area. That wound was squirting blood and went ignored by the goblin; that alone would have killed him pretty soon, but not soon enough.

That 9mm slug was fired early in the fight and got scapegoated...the fact is, a lot more went wrong...like the Feds leaving their armor in the trunks and their main guns on the seat next to them so when they all went skidding to a halt their main handguns by and large were out of the fight and it was mostly backup weapons used.

Remember guys, 1986 was during a low point in the professionalism of most of the armed federal agencies. Morale and training were low, civil rights violations were high. This was the age of Ruby Ridge and Waco.

So yeah, they needed something to blame and put a lot on that otherwise respectably-performing slug fired from one of the only full-sized fighting handguns the FBI had in the fight.

9mm+P and +P+ tech has come a long way since then.
 
In the long run Jim, they blamed everything except the 10mm.

Professionalism, BTW, is a personal matter. You can't paint with quite that broad a brush.

The 9mm Silvertip was a low penetration HP as is the .45/185 Silvertip. This was by design. The bullet in question did pretty much what LE had been howling for since the sixties. A few of us resisted that trend, which is described succinctly here:

The fear of over-penetration is a misconception, which was created back when law enforcement was trying to overcome misinformed public resistance to the use of hollow point ammunition. In the process, we began to believe it ourselves.
Click to expand...
http://www.firearmstactical.com/pdf/fbi_10mm_notes.pdf

While I don't agree with every statement contained in that document, I'm pretty sure they got that right.
 
Quote:
+P does not have a rating, it simply means over pressure and since it has no specified limit, it is impossible to say it is ok in any gun (although your wiki's will try to give it a range, it has none.)

This is incorrect. While CIP does not recognize a +P designation in any caliber, SAAMI does recognize such a designation for .38 Special, 9x19, and .45 ACP and the designation means that the cartridge in question is loaded up to 9-10% higher pressure than maximum standard pressure (.38 Special is 18,500psi or 9% over standard, .45 ACP is 23,000psi or 9.5% over standard, and 9x19 is 38,500psi or 10% over standard). Also, most SAAMI member companies label their .38 Super Auto ammunition as +P even though it is loaded to standard pressure in order to discourage its use in a gun chambered for the lower pressure, but dimensionally identical, .38 ACP cartridge.
Click to expand...

One point that pgdion and many other may not understand is that SAAMI and CIP measure pressures differently whether it be by CUP or PSI / transducer.

The point is that NATO spec. ammo in 9mm is hotter than the standard pressure ammo in both systems.

pgdion wrote: The biggest problem here I think is using a wiki for a source.
Click to expand...

Perhaps you missed my little disclaimer about using Wiki. However, their cited sources are in order. Many if not most of you may not (probably do not) have access to the databases I do (perks of my employer). I can look up STANAG, Mil Spec., and several others but since these are subscription services, I can not link to them (copywrite / license issues, etc.). However, the sources are cited at the bottom of the article and you can sign up to the service that houses these documents. If you want to blindly call me out that's your perogative. If you wish to be intellectually honest read up a bit then decide. As an example from the Wiki Bibliography they cite this document DTIC Document

Edit to add: If you want to see a predecessor document to the STANAG look up MIL-C-70508 (AR) Titled Cartridge, 9MM, Ball, NATO, XM882 date 7 February 1985

Sig's and Rugers are rated for NATO spec. so by definition they are also rated for +P ammo (SAAMI +P); actually the manuals for both my Sig and Ruger state they are rated for SAAMI, CIP, +P and NATO spec. ammo. Just because the Smiths aren't doesn't mean by extension that the rest aren't. Not all of the manufacturers make their weapons that close to the margins of safety.
 
Last edited:
I have had the misfortune to see actual people shot with both the 9mm +p+ and the 357 Magnum.

They both worked just fine. I am no fan of the 110 Grn 357 load, it is loud, underpentrates due to fragmentation and is hard on guns.

The 125 Grn 357 in the full power loading is a beast. Everything heavier usually overpenetrates the average sized goblin. I have seen the 145 Grn silvertip come out the size of a quarter.

As several people here have stated, its the man (or woman) not the bullet.

It is easier for a moderately skilled shooter to make good hits with a 9mm than a 357 magnum. Don't forget the blast of the 357 works both way's, you have an edge because you are expecting it when you pull the trigger.
 
That 9mm slug was fired early in the fight and got scapegoated...the fact is, a lot more went wrong...like the Feds leaving their armor in the trunks and their main guns on the seat next to them so when they all went skidding to a halt their main handguns by and large were out of the fight and it was mostly backup weapons used.
Click to expand...
Jim that is true. There were a lot of things that went wrong in the gun fight. The Winchester 9mm they use did its job. But it was not good enough.


Quote:
The fear of over-penetration is a misconception, which was created back when law enforcement was trying to overcome misinformed public resistance to the use of hollow point ammunition. In the process, we began to believe it ourselves.

http://www.firearmstactical.com/pdf/fbi_10mm_notes.pdf

While I don't agree with every statement contained in that document, I'm pretty sure they got that right.
__________________
Click to expand...
I agree with you Sarge. For the most part they were accurate. The only reason I mentioned the Miami Shoot out is the fact the early responses to this thread indicated that the 9mm +P+ is much better than the 357 magnum. I can't buy into this. The 357 magnum has the best modern day "street record" of any round for self defense. Simply put , the 9mm +P+ does not. It looks impressive but the round does not have the history of the 357 magnum.
For me I look at what law enforcement in my area is carrying now. Not many are carrying the 9mm round. I don't think it is the ideal defensive round. Any round is better than nothing. But I prefer a round that has proven track recond for defense. The rest is up to me.
Bottom line: This thread is about which round is better. Too me the choice is the 357 magnum.
Howard
 
Last edited:
Ruger has a similar statement (don't have any Sig manuals) except their list is inclusive rather than exclusive. You could read into it that +P is ok (and at the same time that '+P+' is prohibited). If Sig lacks some form of disclaimer, then fine for them. I don't think it's an indication of a more reliable gun, just one of less paranoid lawyers ;-). The whole point that started this sub-discusion as you will recall was simply I stated that running +P, +P+, ect ammo does not void your Beretta warranty, Beretta says nothing of the sort. They merely caution that the higher energy loads may accelerate the wear on some components in your gun (basically stating the obvious, and this would be true for all guns whether the disclaimer is present or not). That was the original point and I'm merely trying to provide an explanation to the clause ... I give up. :(
 
It is a recognized SAAMI marking however it does not indicate (per SAAMI) an actual pressure. Just that it is over the maximum allowed for SAAMI standard pressures but not by more than 10%. However, since the standard SAAMI pressure is a maximum rating and ammunition will be something under that (and vary by type and brand), the actual amount a +P cartridge will be over a non +P cartridge still falls into the ??? bin. Using 9mm for an example, All you really know is non +P will be under 35000 PSI and +P should be between 35000 and 38500psi. It still leaves this undefined vagueness to it (it's hotter, but you don't know how much hotter) which is why the disclaimer in the owners manuals (note: they don't say it will void your warranty either, they just don't recommend using it).
Click to expand...

OK, so ammo marketed as +P tells me that it's pressure is within a specified range (in the case of 9mm 35,000 psi to 38,500 psi) rather than an exact number, so what? If I have a gun that is rated to handle 9mm +P ammunition, I can be assured that gun is capable of safely handling chamber pressure up to and including 38,500psi. If a particular 9mm +P loading yields the ballistics I'm looking for, I don't really care what the pressure is so long as it's no more than 38,500psi. Pressure does not necessarily correlate to velocity due to differences in primers, powder burn rates, and the density of bullets so a cartridge's chamber pressure is a rather poor indicator of terminal performance.
 
From Ruger P89, P90, P94, P944 manual page 12 found here: Ruger Manual "The Ruger P Series pistols are compatible with all factory ammunition loaded to U.S. Industry Standards, including high velocity and hollow point loads, loaded in brass, aluminum, or steel cartridge cases. No 9mm x 19, 45 ACP, or 40 S&W manufactured in accordance to NATO, U.S., SAAMI, or CIP standards is known to be beyond the design limits or known not to function in these pistols."



See page 107 for 9mm 9mm+P SAAMI Document

There is no inference here, Ruger is stating that 9mm +P is safe to use in their pistols. 9mm +P is a SAAMI recognized "High Velocity" round; they even list 45 ACP +P. This info is easily available if people wish to look for it.

Of course you could try to prove me wrong, but to get the latest, you will have to purchase the latest document from American National Standards Institute aka ANSI. Yes SAAMI specs are housed under ANSI.
 
I have absolutely no concerns about the fact that I currently have my daily carry G26 loaded up with Ranger 127gr +p+ hollow points. Also have my nightstand G17 loaded with the same ammo.

I really don't believe that either +p or +p+ is necessarily any better for s.d. purposes than any good, commercial hollow points. I just saw a good price on the Rangers and decided to load up with 'em.

As to the post about higher-pressure 9mm ammo causing the slide to cycle too fast in some pistols, there's a pretty simple fix for that. It's so simple that I won't insult anybody by posting the fix. :cool:
 
BB 147gr +P+ in my CZ Rami. I wouldn't feed it a steady diet of that, but since I've chosen to go to all 9's I want the heaviest bullet possible. And it still scoots along at a pretty good pace. For anyone who has NOT shot a Rami 9 in alloy......don't shoot one unless you have $ome $ to $pend because you're gonna want one. I've had 5 S'fields, 4 Kahrs, S&W MPc's, Para, Sig, Kimber...and the Rami is the sweetest gun I've had yet. It's dimensions are almost identical to the Glock 26, but it's heavier. It's a breeze to carry.....sorry for the thread jack.....forgot that this is an ammo thread.
 
jreXD9
Senior Member

Join Date: November 11, 2009
Posts: 247
BB 147gr +P+ in my CZ Rami. I wouldn't feed it a steady diet of that, but since I've chosen to go to all 9's I want the heaviest bullet possible...
Click to expand...

I know of lots of 9mm guys that want a light/fast load but I too prefer the heavier bullet. I have cut the difference (for now) and switched over to Honady's Critical Duty 135gr +P load--Tests look virtually utopian-like.

-Cheers
 
You must log in or register to reply here.
Back
Top