[glockmon]

Does anyone have one or know of any on the net ? I can't find any.

[Jim Watson]

Chart? How about arithmetic?

Power factor is muzzle velocity in fps times bullet weight in grains, divide by 1000 to get down to a three digit number (for IPSC, IDPA leaves it in the long form.)

Example 1. .45 ACP hardball 230 grain bullet at 850 fps; 230 x 850 /1000 = 195.5
Example 2. 9mm P hardball 115 grain bullet at 1150 fps; 115 x 1150 /1000 = 132.25

For competiton purposes, "major power factor" is 165+, "minor power factor" is 125 - 164.99. Actual velocity will be chronographed at major matches, catalog numbers are usually inflated from being shot in test barrels.

[glockmon]

Thanks for the info . I figured after years and years and years someone would of thought of such a thing . Not everyone has access to a chrono. I guess this will be something new for someone to do.

[Sam1911]

Thanks for the info . I figured after years and years and years someone would of thought of such a thing . Not everyone has access to a chrono. I guess this will be something new for someone to do.

If you don't have access to a chrono, no chart in the world is going to help you. You need to know what your gun does with your ammo, and they're all different. If you're just shooting club matches (where they mostly don't chrono your ammo), most factory ammo (except for .38 Spc.) will get you at or above the Power Floor or Power Factor. If you're reloading, you can trust the load books to get you pretty close if you stay on the upper side of the reccommended load range and don't try to cut it close. Again, this is good enough if you're just getting into the sport and no-one's checking.

If you're traveling to sanctioned/major matches, paying the high entry fees, and have a lot riding on your ammo -- a chrono is a reasonable investment. At the very least, you should be able to borrow a quick minute with one from one of your practice buds to test your loads in your gun.

But, no, there is no universal chart, and there really couldn't be one. The onus is on the shooter to do his/her homework.

-Sam

[atblis]

Here's a chart FWIW. IIRC, major has a minimum bullet weight of 124 gr.
http://filebox.vt.edu/users/atblis/PF_chart.pdf

As said before, pull out your calculator and
(bullet weight in grains) x (bullet velocity in FPS) / 1000

EDIT: Are you asking about load data? Because there are forum posts with collected loads that meet power factor. What cartridge and gun are we talking here?

[eerw]

in IPSC open div. major has a minimum 120gr bullet weight, in USPSA its 112gr.

[chbrow10]

Atblis,

Go Hokies!!

Class of 2000.