Power factor (shooting sports)

Power factor (PF) in practical shooting competitions refers to a ranking system used to reward cartridges with more recoil.

Power factor is used in competitions sanctioned by the International Practical Shooting Confederation (IPSC), United States Practical Shooting Association (USPSA), Bianchi Cup, Steel Challenge and International Defensive Pistol Association (IDPA).

For all major practical shooting competitions, claimed power factors are checked by firing the competitor's gun and ammunition through a chronograph.

The most common practice is for a competitor to provide a certain number of rounds to the Range/ Safety Officers at the beginning of the match day.

If a competitor claims major power factor and fails to achieve it, they are moved to minor and their targets are scored accordingly.

If a competitor fails to make minor power factor, they generally can continue to shoot the match, but will do so for no score.

The power factor also doesn't take into consideration any angular momentum or torque, i.e. any lever arm caused by an offset between the bore axis of the firearm to the contact point on the shooter.

The minimum power factor rule is designed to mitigate the speed and accuracy advantages of smaller calibers.

Setting a minimum power factor value requires recoil management skills by all competitors.

In both the open and standard rifle divisions, minor power factor is dominating due to less recoil, and 5.56×45mm/ .223 Rem is a common caliber.

Ammunition loaded to major power factor such as 7.62×51 mm/ .308 Win has a bigger recoil impulse, and is regarded as having an advantage on stages with targets at long range.

[10] To correlate with commonly available ammunition for firearms within a given division, revised power factors were established, effective 1 January 2017.