Major and Minor factor are the two power factors floors recognized in IPSC. Thepower factor of a firearm is calculated using the formula of Bullet Weight (grains) times Velocity (feet/second) divided by 1000.

Minor Power Factor is 125 and Major is 165 in USPSA competition. Production Division is the only division that forces all competitors to be scored minor power factor so all the other divisions are acutely aware of making sure they get the scoring advantage of this higher recoiling ammunition.