Talk to me about +P ammo

[wrinkles]

There is a SAAMI spec for +p there is no spec for +P+. For example 9mm standard=35,000psi, +p=38,500psi so +P+ can be anything over 38,500 like say 38,501 or 50,000

[JMO]
According to the terminal ballistics experts the ,same ones that help design self defense ammo, and several federal studies, the only thing that reliabley stops an attacker is bullet penetration and bullet expansion. The bullet must penetrate deep enough to reach vital organs (at less than optimal angles) and it must make a large hole in order to promote rapid bleeding. Barring a central nervous hit bleeding it the only other reliable stopping mechanism in a pistol round. There is no "shock" or "knock down" factor the bullet will not tear or crush any more tissue via shock or velocity it only wound by what tissue comes into contact with the bullet itself. Having said that a bullet that expands, and penetrates a minimum of 12" in calibrated ballistics gel which studies have shown very closely relate to the penetration and expansion to real life officer involved shootings, is all that is need. There are several +p and non +p rounds that meet this performance so I've never seen the need for +p+ ammo and I prefer the heavier bullet at standard pressure because gives less muzzle blast.
[/JMO]

[Excaliber]

There is a SAAMI spec for +p there is no spec for +P+. For example 9mm standard=35,000psi, +p=38,500psi so +P+ can be anything over 38,500 like say 38,501 or 50,000

[JMO]
According to the terminal ballistics experts the ,same ones that help design self defense ammo, and several federal studies, the only thing that reliabley stops an attacker is bullet penetration and bullet expansion. The bullet must penetrate deep enough to reach vital organs (at less than optimal angles) and it must make a large hole in order to promote rapid bleeding. Barring a central nervous hit bleeding it the only other reliable stopping mechanism in a pistol round. There is no "shock" or "knock down" factor the bullet will not tear or crush any more tissue via shock or velocity it only wound by what tissue comes into contact with the bullet itself. Having said that a bullet that expands, and penetrates a minimum of 12" in calibrated ballistics gel which studies have shown very closely relate to the penetration and expansion to real life officer involved shootings, is all that is need. There are several +p and non +p rounds that meet this performance so I've never seen the need for +p+ ammo and I prefer the heavier bullet at standard pressure because gives less muzzle blast.

[/JMO]

Actually, there are 3 ways to achieve a knockdown or stop:

1. Central nervous system strike (e.g. brain stem) - instant shutdown, end of story.

2. Perforation or laceration of major blood vessels sufficient to cause hypovolemic shock (loss of so much blood that the heart is unable to provide sufficient blood pressure to maintain the brain and central organs) which results in unconsciousness and / or death. This can happen either rapidly with a hit to the aorta or other primary vessel, or more slowly with smaller vessels. Expanded projectiles make larger holes and thus may theoretically injure more blood vessels and / or allow blood to escape more rapidly than smaller projectiles that make smaller holes in the same part of the body.

3. Damage to a major skeletal member (e.g. spine or pelvis) to the point that it no longer supports the body upright and prevents walking or running. This will result in "knockdown" (inability to remain upright) and loss of mobility but not necessarily incapacitation, depending on exactly what is damaged and how.

[wrinkles]

The spine would be considered CNS hit and pelvis hits tend to punch holes through the bone and not break it.

http://m4carbine.net/showthread.php?t=20649

[jester]

It seems there are also a lot of psychological stops but I'm not sure what relevance that has to shooting hot subgun ammo in a pistol.