[ampleworks]

Its not much of a result but its alright I suppose.

For those looking for USPSA power factors, the floor for 125PF is 855fps using a 147gr bullet.

Federal American Eagle 147gr
Factory advertised: 960fps
Shots: 932, 928, 922, 934, 921

CCI Blazer 147gr
Factory Advertised: 985fps
Shots: 932, 959, 935, 931, 919

WWB 147gr
Factory Advertised: 990
Shots: 952, 942, 946, 937, 938

This was out of a 4" XD-9, tempature around 70.

I plan to do alot more shooting of different retail ammunitions to just see the differences. Especially +P types...of course as money allows

 

[TrickyVic]

Huh, do you mind explaining what a chrono is? and what do those numbers represent? thanks in advance

 

[R Dub]

FPS: feet per second (speed)
PF: Power Factor. PFS times bullet weight (gr) divided by 1000.

960 fps X 147gr = 141120 / 1000 = 141.12 or 141 PF

Chrono (chronograph). Instrument used for measuring ballistics data.

 

[sintax]

so the bullet is fired from one end of the device through the other end? I assume it measures the time it takes to get from the first metal band to the back one?

 

[ampleworks]

Think of it as a drag strip for bullets. Between the lights is a preset distance, the time it takes for the bullet to break one light beam until the other, then the machine divides the time and gives you ft/s or m/s

 

[USMC-PRIDE]

Are the factory loads like that, always that far off the advertised FPS?? Or is this pretty standard numbers?

 

[R Dub]

The factors that affect the results the most are temperature, altitude (air density), and barrel length. Most, not all, factory ammo test are completed using a 4" barrel pistol and typically in a controlled environment. Performance will vary some based on the shooting conditions where you live.

Its not uncommon for competition shooters that reload their ammo to have problems because they reload (where they live) to just meet the minimum major PF. Then they travel to another location for a big match and their ammo will chrono below the minimum major PF because the shooting conditions are different. This bumps them down to the minor PF scoring scale. (Not to imply I have personal experience with this. )