# Power factor treshold of 125



## mccoy (Dec 31, 2007)

I'm thinking about participating into some shooting contests.

In IPSC I'd start as a loser, since here they are very competitive and in the revolver division reloading times are critical. Only the S&W 625 in .45 ACP guarantees you a satisfactory performance, and many if not everyone accuratizes it.

There is another association though, which detached from IDPA, they focus on defense tactical shooting, I may have a chance here.
in revolver division only requirement is, in addition to a max barrel lenght of 6", a minimum power factor of 125.

Can you estimate, even roughly, if a 158 grs bullet loaded with VVN340 or other powder, in 38 sp is going to have probs with such a treshold??

Any alternative in .38 sp (might use .357 brass with mild loads they are longer though and harder to reload)??

Presently I don't have a cronograph to measure bullet's velocity.


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## Mike Barham (Mar 30, 2006)

IPSC's power factor is the simple formula of bullet weight (in grains) multiplied by velocity (in feet per second) and divided by 1000. You need your 158gr bullet to hit 792fps, minimum, to "make minor." This is absolutely no problem at all, and can be done with practically any powder suitable for use in .38 Special. 

Always build in a little extra velocity when you're on the borderline. Being disqualified from a match before you even get to shoot really sucks.


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## gmaske (Jan 7, 2008)

Do they they allow speed loaders? That would speed things up a bit. Slip this in and twist the knob and you got a fresh 6 ready to go.


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## TOF (Sep 7, 2006)

I have some chrono data that might help.

158 Grain Bushwhacker Hard Cast SWC in Winchester Magnum cases with 5.7 Grains of Vitavuori N340, Remington Small Pistol Primer yielded 912 FPS from my 4" GP100. Power Factor = 144

More than you need but still a comfortable load. It will take steel down better than 125PF.

Everything the same except Bullet = Zero SJSP: Velocity = 854 FPS or 134 Power Factor.

I have been loading for Major (165PF) so haven't fine tuned a Minor load.

It takes nearly 8 Grains of N340 to hit Major.

I am still playing with different loads.

I bought a pound each of N320, N350, N105 and N110 but it looks like I will stay with N340 as my broad use powder for 9MM, .357 and .40 S&W.

:smt1099


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## TOF (Sep 7, 2006)

mccoy,

You will never be a loser just because you try something new with equipment handicaps.

I have been shooting my GP100 in our IPSC shoots and although I may come in with the slowest score, I consider myself a winner. You are a winner whenever you put out the thought and effort to learn something new or to improve on something you don't do well yet. The only challenger I have is myself.

Purchase 6 or 7 speed loaders and belt clips to hold them then learn how to use them. 

We will be seeing you on the International News in a year or so collecting your big trophy.

Just do it and have fun in the process.

:smt1099


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## Mike Barham (Mar 30, 2006)

*TOF* speaks much truth. Competition is very often about bettering your own score, and beating yourself compared to the last match. Don't go out there and compete with anyone but yourself...at least for a while. Watch the better shooters and learn! Living in Arizona as I do, with shooting luminaries like Rob Leatham (I once ran into him in a grocery), Matt McLearn, Matt Burkett and others gives one an excellent sense of humility.

*TOF*, you'll be getting a package in a day or two. :mrgreen:


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## TOF (Sep 7, 2006)

Matt McLearn lives in Payson and is a regular at our monthly shoots. He puts on quite a show. Some of our other shooters keep him on his toes though but not me. I'm the old fat slow guy that gives them a rest period while I stumble through the course. :anim_lol: 

You have me all perked up and waiting for the delivery guy Mike.

:smt1099


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## mccoy (Dec 31, 2007)

Thanks folks for the tips !

Of course I'm going to shoot for fun but, what the heck, some healthy competition won't hurt and if I can start without many penalties or handicaps so much the better.

IPSC and IDPA only allow you 6 rounds in the cylinder, no matter what its capacity, whereas in this new federation every number is allowed (mine holds 8 rounds).

Great news about the 125 PF, sure I'll try to build some safety margin into it but am glad I can use the 38 specials I've grown accostomed to.

Somewhere I read people will compete with .38 short colts to make reloading easier, but I never saw such a caliber and do not know if ti is avilable over here and if it is eally advantageous.

Full moonclips are allowed (speedier I reckon than gmaske's speedloaders), I'm starting to research into it, it's another convoluted aspect, the 8-shot FMCs come into slightly different thicknesses which adapt to different manufacturers brass, you take one which is not well suited you are going to have a hardish time reloading. Plus you need a demooner tool...

Rob Leatham is known as the absolute best in his own category, isn'it? Very accurate shooter, saw a clip of him in youtube, just awesome.

TOF, you competing with you ruger is sure a hot thing!!

8 grs of powder in a .357 mag sounds like a lot, that's why the .45 ACP is the favourite revolver caliber in IPSC I reckon, it easely makes major, has allegedly reasonable recoil and goes very easily down the wheelchambers...


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