Why 9mm +P and +P+ ??

Seems to me if you have a 9mm and are stuffing +p+ thru it, why not just buy a .40cal? Or, is there something I'm missing?
Perhaps the need for extra punch is just temporary. Why buy and learn a new gun for a short term need?

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When it comes to bullet diameter, as in hot rod engines, there is no replacement for displacement.

Going to +P is thought to improve the lethality of the 9mm, but I am not convinced it does. Raising the velocity may improve expansion and penetration, but the pressure increase will cause its own problems. Pressure is not your friend, at some point in the future, it will reach around and bite you.
 
Mind you, that's also why there's such a thing as a 147 grain 9mm bullet.

Ummm.... not quite. The 147gn 9mm was designed for use in conventionally suppressed guns. A 9mm subgun (with a longer then pistol length barrel, the Uzi has a 10” barrel) shooting 115/124gn ammo is still quite loud with a suppressor due to the supersonic crack

The heavier 147gn stays subsonic in all but the longest barrels.
 
When it comes to bullet diameter, as in hot rod engines, there is no replacement for displacement.

Going to +P is thought to improve the lethality of the 9mm, but I am not convinced it does. Raising the velocity may improve expansion and penetration, but the pressure increase will cause its own problems. Pressure is not your friend, at some point in the future, it will reach around and bite you.

What problems will pressure cause? How long will it take for those problems to show up?
 
All this is exactly why I settled on the 357 Sig...

9mm +P+, and then some (very near 357 mag)... In a pistol rated for that level of pressure, yet is the same size as the 9mm.

Glock 32... The perfect high powered 9mm.

Glock 19 in size, dang near 357 mag in power, and still holds 13 rounds...15 rounds with full size mags.

Easy to shoot, hits hard... Is a little loud, but its not too bad from 4" barrels.
 
Seems to me if you have a 9mm and are stuffing +p+ thru it, why not just buy a .40cal? Or, is there something I'm missing?
Cheapshooter made the best cogent comment in my opinion...capacity...otherwise, I'm of the bigger is better crowd insofar as CC is concerned.

As to the supposed add'l recoil of the .40, hasn't been detrimental in my training...time loss to the 2nd shot (split time) of a controlled pair is measured in split seconds, and I doubt that the small difference is measurably more effective in any verifiable way, in actual street combat/confrontations.

But there are many here on TFL that find the add'l capacity in a side arm of the same size, a positive advantage over the .40's larger bullet. So, to each, his own.

Best regards, Rod
 
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I shoot my 40's just fine. If other folks don't like them, hopefully they don't have to shoot them.

If I felt 9mm wouldn't do the job, I would just switch to 40 or 45.

Personally, I feel fine with any of the major service calibers. It's nice that most of us have choices.
 
What is labeled as +P in this country is really just standard 9mm ammo in the rest of the world. For what ever reason 9mm has been loaded on the light side in this country. Typical loads are a 115 gr bullet at around 1100 fps. When the military adopted the 9mm pistol they also adopted the standard European load of a 124 gr bullet at around 1200-1250 fps. From some 5" barrels that load will reach 1300 fps. In this country they label that as +P or +P+. It shouldn't be in my opinion. Maybe standard loads should be labeled as 9mm "Lite".

And that by the way is just about where a typical 125 gr 357 mag loads from a 4" barrels are. I know that there are newer, hotter 357 mag loads that will beat that, but the real world speeds that cops were getting in the 1980's when the 357 mag earned it's reputation as a fight stopper was 125 gr bullet at about 1250-1300 fps. They are advertised at 1500 fps from 8" barrels, but I'm talking real world speeds from the 4" revolvers actually carried.

When you can get the same performance as the well respected 357 mag from a smaller handgun, holding 3X as much ammo with less recoil it has to be considered.

In the 1980's when the FBI briefly adopted the 10mm and later the 40 S&W the 9mm loads they were considering were the typical anemic loads common at the time in this country. Compared to those loads the 40 was an improvement.

After the military adopted the 9mm, and the European loads, it opened up some eyes to what the 9mm was capable of. Those same loads with HP ammo doesn't give up anything in the real world to 357 mag revolvers loaded with 125 gr ammo. The 357 Sig just makes up that last 50 fps putting it exactly where 357 mag is, but with reduced ammo capacity and more recoil. To me it isn't worth the disadvantages for 50 fps.

The 40 isn't a bad round either. With the best loads it does everything a 357 mag does with 158-180 gr bullets. Realistically today the only reason to choose 40 vs 9mm is do you want to shoot 125-147 gr bullets, or 155-180 gr bullets. For personal defense most people are finding 124-147 gr bullets are just fine and if heavier bullets are needed they are skipping right over 40 and going to 10mm.

But it took a while to convince people, and many are still not convinced. But this is why 9mm has really come on strong in recent years and is replacing the 40 for LE use. The capability has always been there. But bias and old school thinking that you had to use a larger caliber prevented it from being considered until recent years.
 
So-you're going to (ouch!) get shot from 20' in the torso with one round from a handgun.

They give you the choice of 9MM or 9MM +P. Are all you 'it's a marketing scam' really going to not care which they use? :)


Larry
 
When the military adopted the 9mm pistol they also adopted the standard European load of a 124 gr bullet at around 1200-1250 fps. From some 5" barrels that load will reach 1300 fps. In this country they label that as +P or +P+. It shouldn't be in my opinion. Maybe standard loads should be labeled as 9mm "Lite".

Do you have any reference for this?

I am under the impression the new guns will shoot the same NATO spec ammo as the Beretta did: 124 @ 1160 fps

At what pressures will a 124 reach 1300 fps?
 
volkstrm said:
Yea why not just go with the best caliber (IMO) the 357 SIG?
  • Magazine capacity usually equal to .40 S&W and less than 9mm. (In fact, many common service pistols use the same magazine for .357 SIG and .40 S&W.)
  • Doesn't require another pistol and the requisite additional mags.
  • .357 ammo is expensive and can be hard to find.
FWIW I'm just regurgitating these commonly parroted reasons, NOT agreeing with them; I'm usually one of the first people to make your argument! :) IMHO most people who use large quantities of 9mm+P+ are asking for trouble.
 
Do you have any reference for this?

I am under the impression the new guns will shoot the same NATO spec ammo as the Beretta did: 124 @ 1160 fps

At what pressures will a 124 reach 1300 fps?

With the right powder (3N38), one can reach 1300 fps within normal operating pressure. That's with a bullet at or near the maximum OAL. For shorter OALs, it might exceed the pressure limit, depending on the bullet.

Vectan SP2 might be able to do that, too. Would love to try some.
 
When it comes to bullet diameter, as in hot rod engines, there is no replacement for displacement.

Going to +P is thought to improve the lethality of the 9mm, but I am not convinced it does. Raising the velocity may improve expansion and penetration, but the pressure increase will cause its own problems. Pressure is not your friend, at some point in the future, it will reach around and bite you.


What problems will pressure cause? How long will it take for those problems to show up?

High pressure can and does cause a huge number of problems. Blown case heads were rather common in S&W 40's. Blown primers that get lodged in the mechanism. Notice the trend to crimp primers on everything?, because primers are coming out and jamming the mechanism. Failure to feed, where the slide jams on the middle on the top cartridge because it was moving too fast. Failures to eject, the rim gets ripped off. Cartridges that are operating at the top of a pressure envelope are very sensitive to increased temperatures, case construction, changes in seating depth, case protrusion, etc. You will have fewer problems if you can do the same job at a lower pressure.
 
High pressure can and does cause a huge number of problems. Blown case heads were rather common in S&W 40's. Blown primers that get lodged in the mechanism. Notice the trend to crimp primers on everything?, because primers are coming out and jamming the mechanism. Failure to feed, where the slide jams on the middle on the top cartridge because it was moving too fast. Failures to eject, the rim gets ripped off. Cartridges that are operating at the top of a pressure envelope are very sensitive to increased temperatures, case construction, changes in seating depth, case protrusion, etc. You will have fewer problems if you can do the same job at a lower pressure.

The 40 S&W blowout were a problem in Glocks in which the barrels offered little case support, so it's not a +P pressure problem in that case. It's a problem with proper case support and weak brass with standard pressure ammo. https://thefiringline.com/forums/newreply.php?do=postreply&t=593147

If primers are blown out of the case in a pistol round, you're way hell above +P operating pressures, into the land of excess rifle pressures, or have crappy headspace. According to this source (https://squibloads.wordpress.com/reloading/get-the-crimp-out/), the primers are crimped in military ammo to keep the primer in place in barrels that can have loose headspace. And to help keep them in place during rough transport over long periods of time. See this: https://www.thehighroad.org/index.php?threads/purpose-of-crimped-primer-pockets.618616/ And this: https://www.quora.com/What-are-crimped-primers And this https://detroitammoco.com/removing-primer-pocket-crimps/

If high pressure itself was a cause of blowing primers out of the case, then every cartridge above XX,XXX (select your limit) pressure would be blowing out primers all the time. Yet many cartridges have very high pressure limits, such as the 9X23 Winchester (55,000 psi), 221 Remington Fireball (60,000 psi), 327 Federal Magnum (45,000 psi), 356 TSW (50,000 psi), 357 SIG (40,000 psi), 454 Casull (65,000 psi), 460 S&W (65,000 psi), and 500 S&W (60,000 psi), and that's just handguns rounds. Rifle round are routinely 55,000+ psi.

Rarely does commercial ammo have crimped primers. The handgun rounds that have it are almost always military surplus, like the 9mm. In most military ammo, crimped primers are common, for the reason cited above.

Failures to feed as you describe are an issue with slide velocity, not chamber pressure itself. You can have those malfunctions from simply having a mismatched recoil spring, or weak magazine spring with standard pressure ammo. The rule here is to match how the gun is tuned to the recoil force of the ammo.

Cartridges that are operating at the top of a pressure envelope are very sensitive to increased temperatures, case construction, changes in seating depth, case protrusion, etc.

We agree here.
 
There were changes in pistols as they went from 9 to 9+P, to +P+. Some of those changes were never advertised ,some needed to read instructions [not for use with +P. ] different steel, larger dimensions ,etc.
You can always shoot a +P in a 9 but the wear and tear will be greater as velocities go up.
 
For competition to keep up with the 38super and 9x25 dillon...not to mention there are modern firearms that can handle the pressure and bullets to handle the speed.
 
For competition to keep up with the 38super and 9x25 dillon...not to mention there are modern firearms that can handle the pressure and bullets to handle the speed.

Most 9mm+P and +P+ factory loads won't make Major power factor. There are some companies that load 9mm to Major power factor, called 9 Major, but they aren't the big brand names. And they say to only use them in Open class competition guns that are specially designed for that purpose, whereas off the shelf +P can be fired in many commercial non-competition guns.
 
As to the supposed add'l recoil of the .40, hasn't been detrimental in my training...time loss to the 2nd shot (split time) of a controlled pair is measured in split seconds, and I doubt that the small difference is measurably more effective in any verifiable way, in actual street combat/confrontations.

WHOA Nellie. You better watch posting your observations based on Emperical data when we are trying to point out that the soft 9mm recoil really doesn't make as much of a difference as some try to claim. Stand by for someone to jump in and assure you that their casual observation of different shooters, of unknown and unmeasured skill levels, standing on a firing line indicate to them that 9mm is MUCH faster in follow up shots. So much so that it could make or break a street SD shooting. Much more than the potentially better (albeit slightly) better wounding capacity of .40 or .45.

In another thread several posters, ones who actually measure split times (you know, because using something actually measurable might be useful) seemed to show an average split time difference between 9 and 45 that would equal to 9 rounds of 45 to 11 rounds of 9mm in the same time. What hurts more, 9 rounds of 45 (or 40) or 11 rounds of 9mm? Answer? All of the above. The greatest 9mm advantage is capacity, but a large advantage it is.

As to the OP. There is nothing wrong with occasionally practicing with +p and using it for carry. It will not make a huge difference, but I'm of the opinion that it could possibly help... Some... Maybe. +p has an actual saami pressure defined. +p+ does not, and I advise staging away from it because of that.
 
74A95 - OK. So what. People have been trying to stoke up the 9mm for years. The question was why the +p+. Not will a +p+ make major. BuffaloBore puts out a +p+ 124 @ 1300 and a 115 @ 1400. That's pretty close to a 38Super, which is what I stated.
 
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