Energy, TKO, OGW and IPSC PF
Energy, or more correctly, the Kinetic Energy, is calculated from
the bullets weight and velocity.
Taylor Knockout Formula, as it misleading stands for, calculates
a “knockout” factor based upon the velocity, bullet
weight and caliber. The TKO formula favors larger calibers with
heavy bullets, rather then small bore and high velocity calibers.
When used on conventional rifle calibers, the TKO formula will give
you a value for comparing different calibers and loads.
The OGW is an abbreviation for Optimal Game Weight formula. Compared
to the TKO formula, this will give more credit to faster bullets,
but will also favor heavier bullets. The OGW result indicates the
maximum animal weight this caliber and load would effectively kill.
This IPSC Power Factor is an index that tells us if the momentum is bellow or above the Minor/Major class limit.
The Minor class is for rounds with a PF larger then 150 and below 320.
The Major class is for rounds with a PF larger then 320.
Keep in mind that these formulas is a rather simple way of giving
different loads and calibers a comparing index, not an exact value
for how effective it is against a specific animal. Shot placement,
bullet quality and distance (remaining speed of the bullet) are
also essential criteria that will affect the “killing power”
of a bullet.