What is +P?

by
posted on February 21, 2017
** When you buy products through the links on our site, we may earn a commission that supports NRA's mission to protect, preserve and defend the Second Amendment. **
winchester-9mm-op.jpg

SAAMI, the Sporting Arms and Ammunition Manufacturers' Institute, sets standards for chamber and ammunition dimensions and ammunition pressures in the United States.

Voluntary adherence by makers assures the shooter that all ammo will fit and safely fire in all firearms for which it is intended. SAAMI lists a few handgun cartridges at higher-than-normal standard pressure, called “+P.” Note that “higher pressure” does not mean “high pressure.” These +P loads in 9mm, .38 Special and .45 ACP are only nine to 10 percent above standard SAAMI pressure—nowhere near approaching magnum loads that might be twice that of the parent design. Note that these cartridges are all 100 or more years old.

Improvements in metallurgy and handgun design make +P loads viable in modern firearms, but shooting +P in older guns could be disastrous, and a steady diet of +P in some modern guns may wear them out prematurely. If your handgun is not marked, “+P,” don’t shoot +P ammo in it until you contact the firearm manufacturer and learn whether it is safe to do so. SAAMI, incidentally, does not have a standard for +P+ ammunition, which various sources list as approximately 18 to 30 percent over SAAMI standard pressure.

Learn more about SAAMI here: www.saami.org.

Latest

2025 Lapuacup 1
2025 Lapuacup 1

Marsh Edges Stine In Canadian Showdown To Win Lapua Monarch Cup Opener

Justin Marsh edges Jake Stine by one point to win the Canadian NRA Smallbore Silhouette Nationals and first stage of the 2025 Lapua Monarch Cup.

Hitting The Bullseye: England’s Bideford Shooting Club’s Big Dream Needs You

Bideford Target Shooting Club in the U.K. launches fundraising drive to build world-class shooting facilities for all ages and abilities.

Silencer Central CEO Brandon Maddox Joins NSSF Board Of Governors

Silencer Central CEO Brandon Maddox appointed to NSSF Board of Governors.

Nicholas Coppage Tops Field At 2025 USA High School Clay Target Nationals

Nicholas Coppage wins 2025 national clay target title after a perfect final round and epic shoot-off, Beaver River Central H.S. receives team title.

New: Metal Madness Easy Up Target Frames

A simpler setup with more affordable gear makes Metal Madness steel shooting more accessible than ever.

NRA Announces Dianna & Ryan Muller As Brand Ambassadors For America’s Rifle Challenge

NRA announces Dianna & Ryan Muller as brand ambassadors for America’s Rifle Challenge program, promoting AR-15 marksmanship, safety and training.

Interests



Get the best of Shooting Sports USA delivered to your inbox.