9mm +p, +p+ ammo ratings
How does the rating system for this kind of ammo work?
I've seen 115 grain ammo rated at "+p+", while seeing 147 grain ammo rated at "+p".
I'm sure there are a number of combination's, but how do they work?
Does a higher grain number mean more power? Or do you just go by the letter and plus signs?
I've seen 115 grain ammo rated at "+p+", while seeing 147 grain ammo rated at "+p".
I'm sure there are a number of combination's, but how do they work?
Does a higher grain number mean more power? Or do you just go by the letter and plus signs?
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Bullet weight really has no impact. You need to understand that for commercial ammunition the Sporting Arms and Ammunition Manufacturers' Institute (SAAMI) has establish pressure limits on virtually every cartridge you are likely to encounter. When you go above these pressures you are at +P or the even higher pressures of +P+. The problem with the +P+ loads is that are that there are no established pressure limits and they can approach what are known as "proof loads", which are the extreme pressures that manufactures use to test firearms barrels for safety limits. Nearly all firearms manufactures will clearly state if there firearms are suitable to use with +P loadings and most will also caution that even though their guns can handle + loads, excessive wear will result from firing too many of these rounds. 0 -
Mark, thanks for the input.
What does the grain number mean then?
How do you know the weight of the bullet?
And are there other letter ratings to go by besides "P"?
Just trying to understand these better for future ammo purchases for different purposes. Home defense, target shooting, etc. I already understand the bullet types, just not the overall classifications/ratings.0 -
quote:Originally posted by floorguy24
Mark, thanks for the input.
What does the grain number mean then?
How do you know the weight of the bullet?
And are there other letter ratings to go by besides "P"?
Just trying to understand these better for future ammo purchases for different purposes. Home defense, target shooting, etc. I already understand the bullet types, just not the overall classifications/ratings.
The numbers 115, and 147 are the weight of the bullet.0 -
Beeramid, thanks.
I wasn't sure, had to ask.
Still learning...0 -
This has been answered, but I'll amplify.
Grain weight refers to the weight of the bullet.
In 9mm luger, a 115 grain bullet is a light one, a 124 grain is a standard medium-weight one, and a 147 grain bullet is a heavy one. While a few other weights do exist, they're not commonly encountered or used.
Without getting into complicated explanations of why, most authorities favor either 124 or 115 grain 9mm luger bullets for defensive use. 147 grain bullets result in slower bullet velocities, less than the speed of sound, and are mostly intended for use in suppressed (ie "silenced") pistols.
"+P" refers to a round that is loaded to about 10% extra pressure, leading to about 10% more muzzle velocity compared to an ordinary cartridge of similar bullet weight. "+P" rounds usually cost more than ordinary rounds, and are intended for defensive use.
Since "+P" rounds are "hotter" than ordinary rounds, they can contribute to increased wear and tear on a gun. While just about all of the modern 9mm luger guns from major manufacturers can handle +P rounds with no problem (eg Glock, Sig, Ruger, Smith and Wesson, CZ, etc) a few of them are not quite as strong, and +P type rounds should probably be avoided.
"+P+" refers to a round that is even hotter yet than +P. The problem with "+P+" as Mark Christian has mentioned is that unlike ordinary and +P rounds, there is no standardized pressure limits for +P+ rounds. Pretty much all gun manufacturers advise against using +P+ labelled ammo in their guns, because it will at least accelerate wear and tear on the gun, and at worst could present a safety hazard to the shooter.
In practice, so-called +P+ ammo may be intended for use in 9mm submachine guns and carbines that by design have stronger actions than pistols. Also, its probably true that SOME ammo labelled as "+P+" isn't necessarily stronger than ordinary +P ammo, with the label just being a marketing gimmick.
For what its worth "proof" rounds are extra-high pressure rounds used to test the integrity of a firearm. (IE to "prove" that they are OK for use). "Proof" rounds generally are calibrated to run at 30% more pressure than ordinary rounds, and in theory, a gun should be able to safely handle a limited number of proof rounds.
Again, in theory, there probably are a number of modern pistol designs that are capable of safely handling large numbers of rounds of that elevated pressure. In practice, you should never encounter "proof" type rounds (ie ordinary manufacturers don't sell them), and if you did, you wouldn't want to use them in your pistol, barring a life or death emergency.0 -
I think alot of the +P+ 9mm ammo that doesnt come in a commerical sales boxes is made for use in submachineguns..
Also I've seen some new made fiocchi 130 grain ammo that was marked +P marketed as for the Luger toggle action..
Buffalobore's +P+ may be an exception..0 -
That should do it.
Thanks to all who answered.
Very helpful.[;)]0
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