Intro: Power Factor

| | Power Factor | USPSA uses what is called a "power factor" (PF) to classify ammo. Your ammo's PF is calculated by multiplying the weight of your bullet (not the entire round) times the velocity of the bullet, and then dividing the result by 1000. The minimum power factor allowed is 125 PF. A standard 9mm factory round, as well as almost all full power .38 Special factory ammo, will make this minimum PF. Any ammunition that meets this minimum PF level and is 9mm caliber or larger will be legal to use in any USPSA competition (either the "Limited" or the unlimited "Open" gun divisions). USPS

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