What does +P mean?

[9mmGuy]

Sorry for the rookie question as i am still relatively new to firearms.

What does +P, or +P+ mean? I have heard a couple things, like plus powder or plus power. And what does it do for ballistics? Faster bullet speeds or more muzzle energy?

i was just buying some defense ammo and saw that, and thought to my self i cant buy that i dont even know what it means...

Thanks for the help

[seamusTX]

The P stands for pressure (at least that's my story, and I'm sticking to it). +P ammuntion produces higher pressure than standard loads, and +P+ higher yet.

These loads will give you more velocity, energy, recoil, and muzzle blast. They can also blow up your weapon if it wasn't designed to hande them.

- Jim

[Liberty]

The P stands for pressure (at least that's my story, and I'm sticking to it). +P ammuntion produces higher pressure than standard loads, and +P+ higher yet.

These loads will give you more velocity, energy, recoil, and muzzle blast. They can also blow up your weapon if it wasn't designed to hande them.

- Jim

I've avoided these, not because I'm afraid they will blow up my gun, but that it will beat it up more than I would like. My gun (I asume) was designed for optimal performance) for standard millitary load. Although it might be safe, the springs weren't designed to perform at such enhanced forces.

[G.C.Montgomery]

Sorry for the rookie question as i am still relatively new to firearms.

What does +P, or +P+ mean? I have heard a couple things, like plus powder or plus power. And what does it do for ballistics? Faster bullet speeds or more muzzle energy?

i was just buying some defense ammo and saw that, and thought to my self i cant buy that i dont even know what it means...

Thanks for the help

In the simplest of terms, it means the cartridge is loaded to push bullets of a given weight at higher than "normal" velocities for standard pressure cartridges of the same weight. This can be done using a larger charge of gun powder or a combination of a larger charge and slower burning powder.

[HankB]

There are "+P" standards for some cartridges, but no officially-recognized "+P+" standards.

For example, the SAAMI standard for Maximum Average Pressure for 9mm P is 35,000 PSI. The standard for "+P" is 38,500 PSI, and is probably close to original, military, or European-standard 9mm ammo. (But instead of SAAMI standards, the Euros use CIP standards, which measure pressure differently.)

The "+P+" ammo I've seen often has a notation that it was loaded to 40,000 CUP. Now, CUP and PSI are not easily converted, but I'd guess (and it's ONLY a guess) that 40,000 CUP stuff was probably around 42-45 KPSI.

Good guns will handle "+P" and "+P+" ammo without danger of blowing up, but wear will be accelerated.

[Skiprr]

The P stands for pressure (at least that's my story, and I'm sticking to it). +P ammunition produces higher pressure than standard loads, and +P+ higher yet.

Jim is always right. the +P cartridges go up to about 15% greater internal pressure than standard, and +P+ up to 25% greater. In newer handguns that don't specifically say they won't handle +P, I wouldn't hesitate to fire it once in a while in practice and to carry it as my defensive round; the extra 10% or 15% pressure improves velocity and stopping power, but it's not so huge an increase as to be damaging to a firearm of relatively recent vintage and in good working order. But read your firearm manual.

That said, I can't think feeding any weapon a steady, case-per-month diet of +P would be a good idea. It'll just shorten the gun's life expectancy...not to mention shorten your bank account.

[Skiprr]

Now, CUP and PSI are not easily converted, but I'd guess (and it's ONLY a guess) that 40,000 CUP stuff was probably around 42-45 KPSI.

Only because it may come up: CUP = Copper Units of Pressure. Here's an interesting pressure load chart from handloads.com, if interested: http://www.handloads.com/misc/saami.htm.