Sunday, October 21, 2012

Power Factor

Vortex cannon - PointlessSites.com

The definition of POWER FACTOR in USPSA is bullet weight, times velicity, divided by 1000. Which to say is:

MV/100 = PF

Or, to use an example, for a .45 ACP "Hardball" (military) round of ammunition:

Bullet Weight = 230 grains
Velocity = 800fps (feet per second)

So the "Power Factor" is calculated as follows:

230 grain bullet, and 800 FPS velocity:
PF = 230 x 800 / 1000
PF = 185,000 / 1000
PF = 185

That's the standard load (circa 1960) of the .45acp in a 1911 Browning-style pistol, using "BALL" ammunition.  And it falls well within the "Major Power" designation, according to the 2008 USPSA Rule Book, which requires a minimum of 165 PF to make "Major Power".

However, if you reload it with 200-grain (semi-wadcutter bullets,usually), you get a recalculated Power Factor ... assuming the same velocity:

200 grain bullet, and 800 FPS velocity:
PF = 200 x 800/100
PF = 160,000 /1000
PF = 160

Unfortunately, USPSA requires a PF of 165.00 or greater to achieve "Major Power".   You can see from this example that you need to work your reloads and then calibrate them, to determine whether you are likely (or not!) to be calibrated as Major Power at a Major Match.

I realize it's difficult to accept that one may be competing in a USPSA match with a .45 ACP cartridge, and still be shooting "Minor Power".

However, that's the way it is.
If you are chronographed as "Minor Power, your A-zone hits will still be with 5 points.  But your B/C-zone hits will be worth 3 points, not 4.

And your D-zone hits will be worth 1 point,not 2.

Well, that's just the way it is.

And of course the "Minor Power" floor is PF= 125.00

Consider a 125 grain bullet being pushed through a 9mm.  In order to achieve Minor Power, that bullet must be choreographed at 1000 fps. 

Oh, and in case you were not aware .. if your PF is under 165, you will be deemed to be shooting 'Minor Power'.

If your PF is under 125, then you are deemed to not meet the Minor Power Factor floor ... and you are shooting 'just for fun'.  Unless you DQ during the match, your scores WILL be recorded .. but they will be recorded as ZERO points for every stage in the match.

Sorry, Charley.  Fun, challenging .. but competitive?  No, hardly.

So what do you think about THESE Guys, with a Vortex Cannon?




Right. Shooting just for fun, and entirely 'not competitive'.

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