Community for Kel-Tec Shooters banner
1 - 8 of 8 Posts

·
Registered
Joined
·
32 Posts
Discussion Starter · #1 ·
Hi,new guy here again.At the (high) risk of sounding stupid,could someone explain to me what the designation +P and +P+ in reference to ammo means.Does it refer to the grain load of a cartridge?Where is the seperation point between a normal load and +P.The ammo my dealer gave me when I bought my gun is 87 grain,but I have seen reference to loads between 80 and 100 on this site.Just trying to wise up.Thanks
 

·
Registered
Joined
·
15 Posts
Overpressure ammunition

I had the same question myself. Here is what I found.

"Overpressure ammunition, commonly designated as +P or +P+, is small arms ammunition that has been loaded to a higher internal pressure than is standard for ammunition of its caliber... This is done typically to produce rounds with a higher muzzle velocity and stopping power, such as ammunition used for defensive purposes."
http://en.wikipedia.org/wiki/+P
 
G

·
again to restate a previous post. There is no +p 380 ammo. That is all mfg-er hype. So just shoot um like u stole um!!
 

·
Registered
Joined
·
9,377 Posts
The +p and +p+ ammo is only made in a very few calibers.
As Jocko has said, .380 ACP is not one of them.

It is loaded to not exceed 21,500 PSI, regardless of what is stamped on the head of the cartridge. This is done in deference to the millions of old and somewhat weak blow-back operated .380 pistols made over the last 100 years, of every known quality level.

In the case of Corbon, it is loaded right up to the 21,500 limit.
On the otherhand, most other brands are probably loaded much closer to 18,000 - 20,000 PSI.

The following *SAAMI specs are for Standard & +P Maximum Allowable pressure levels. (There is no 9mm +P+ SAAMI standard. This is mainly Law Enforcement ammo, loaded to those special  requirements.)

9mm Luger - Std. = 35,000 PSI. +P = 38,500 PSI - +p+ = 42,000 PSI proposed.

.38 Super = Has been marked +P since 1974. It is not truly +P, but is marked as such to indicate it should not be fired in the old .38 Colt pistols. All .38 Super ammo is loaded to 36,500 PSI max., and always has been.

.38 Special = Std. = 17,000 PSI - +P = 20,000 PSI.

.45 ACP - Std. = 21,000 PSI - +P = 23,000 PSI.

In general, +P ammo is loaded with slightly more, and slightly slower burning powder then standard pressure ammo.

This gives a longer pressure curve, which is able to accelerate the bullet to higher velocity in normal barrel lengths.

It may, or may not prove to provide much of a power boost in very short-barrel guns, but does make for a spectacular flash & muzzle blast!
Because of this, most people assume it is more powerful then standard ammo in any barrel length.
Such is not always the case in very short barrels.

*SAAMI = Sporting Arms & Ammunition Institute


rcmodel
 

·
Registered
Joined
·
9,377 Posts
NO.
As far as I know, no such information is available.

The manufactures do no release pressure info, and the only way to get it would be with a .380 ACP pressure test barrel, and a lab full of very expensive equipment.

Anyway, pressure is pretty meaningless.
Velocity is what matters, and although pressure is what makes velocity, it is not a reliable indicator of actual velocity due to the many variables in different powder burn rates, barrel length, etc.

There are Chronograph results posted here from time to time, but I don't have the links.


rcmodel
 
1 - 8 of 8 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top