Major re-think?

Hi there again,
I'm pleased that this thread has sparked off an interesting debate.

Raymonds point about the Neutrons was interesting so I decided to do the calculations. Approximately:

Weight of a neutron = 5.14E-23 grains
Speed of light = 9.84E8 fps
so, by mvv/450240 (a good appoximation)
gives us the energy of a neutron as...

wait for it....

1.1E-10 foot pounds. Virtually nothing in other words. Whew! Still it explains why they don't knock chunks off skyscrapers....

Still I accept Raymonds point about stopping power not necessarily being related to muzzle energy. But I can't accept that it's related to recoil either. Who chooses their loads simply because they recoil more? No-one, I expect. I think my original thesis still stands, which was that power for IPSC should be measured by power rather than momentum. 003 care to comment? Raymond? Anyone else?

Thanks as always to everyone for the great debate! T.S.
 
It was a long time ago I did that computation and I may have had something a little larger than a neutron in mind.

Still the problem I have is that those wanting to change the PF All tend to be trying to push the limits. Yes a 230grain bullet at 760 fps will make major. I don't consisder it an honest load in a .45 pistol.

I can agree that the momentum formula gives too much creedance to bullet weight. But the Foot Pounds Formula gives too much creedance to speed also.

In General it can be said that the rounds that cause more recoil tend to be better stoppers if all else is equal. (ie. bullet design)

Also to make the shooters always looking for that little advantage in the GAME, will make the PF rule so complicated that we have to take a computer to the range with us just to figure the PF.
BTW a 135Grain .40 Cor-Bon make 1300 FPS making 507 Foot Pounds and a PF of 175.5. Gee, that sounds like major to me. A 155 grain at 1205 (factory Win) makes 500 Foot pounds. And a PF of 186.8 and probably about the same recoil.
 
I think there are 3 major reasons the founders went with the way they calcualte pf and the levels.

1. They did not like hi-cap 9mms. Plain and simple. A real man shot a 1911 in .45.

2. They wanted to keep the calculation simple. Some of the folks who posted on this thread understand dynamics, other obviously do not. Energy, Power, Work are all dynamic terms related to each other. Momentum is a simplistic formula that gives us PROPER numbers in some cases. In the real world, momentum is near impossible to find. Dynamic, real physical systems are highly complex with mutiple degrees of freedom, as many as 6. Momentum CAN NOT account for these. Momentum is a starting point in many rigorous engineering problems, but it soon falls by the way side and more powerfull calculations are used.

3. A measure of safety to keep hot-rodders from blowing their guns.

If those were not the reasons, they are now.

Now, the rules are made and maybe we should live by them. But, the rules are in contradiction, they say Power but calculate Momentum. WRONG, minus at least 50% on any test I have ever taken, not just for the wrong number, but for the wrong comprehension and undersdtanding!

I agree that the PF calculation should be altered to reflect true dynamic properties. How this is accomplished is another question.

Who said that the .40 S&W is not proven as a reliable stopper? No disrepect meant, but look at some numbers, have you been in secluson for the past 10 years. Most PDs have or are switching to it and several rounds exceed the best .45 load!

As for ease of calculation, I have shot many mathces and have never had a load chrono'd except at a mjor match where everyone did. The guys keeping score were using calculators and so, really, how hard is it to push 1 more button? How many of you can really calculate (1237*135=pf) in your head? Good thread Scandinavian. Good Shooting, MarkCO
 
Good Observations MarkCO,
Can I calculate PF in my head, No not reliably, I can with pencil and paper though.
easy thing to have at a match, just turn over a score sheet.
As to the .40 being better than the .45, Maybe I haven't seen those states but I'll take your word. Problem all this energy is useless until you take Bullet Design into account. Do we now bring out enough calibrated Balistic Gelatin to the range? And who's standards do we use? Fackler, Sanow, the FBI?
And by the time we test all the bullets for speed weight and Design and get done arguing about what to use as a standard Someone will still have a complaint that you can build, into a reason it's unfair.

Mean while those of use that shoot for training and or Fun will be shaking our heads, but not so hard as to mess up our sight picture as we shoot the COF and enjoy shooting Major and Minor.

PS. I shoot Both, in neither do I shoot the lightest load that makes it. If you want to make money at it then you have to get so good at the Game that the Major/Minor Debate doesn't matter any more. I've never heard Barnhart or the Jet complain.
 
The above discussion was not complaining but rather thoughts about the scale on which to measure the potent of projectiles that is supposed to be rewardable in ipsc type competition.
No spesific limits were named, should one insist using biggest,baddest etc. etc. the energy limit can be set at 20KJ(s=0) so that .50BMG won't make it without excessive pressures.
I really can't understand a point that $4 taiwanese calculator is too much if one can't compute the energy in his mind. And why should one ? If the event participated is of any significance there will A) be laptops present for following the the progress of the competition real time and to provide competitors and spectators with the knowledge of their present standings between stages. B) the "PF" calculation is worry of the organising party anyhow.

For matters of simplification it could be assumed that terminal ballistic behavior of all the bullets is equal, thus leavings us only the energy to worry about.

As seems that many insist on animalistically simple analogues: Fairly stiff load of 5.56Nato makes just about major whereas Nato spec. .45acp load makes it easily. Where can be found those persons that rather get shot with the rifle than the pistol ?

The reason why Jet and Burner don't "complain" about PF is most likely divided in two parts, first of all they're professional gamesmen so it's completely irrelevant to them if they were throwing toilet seat covers at the targets as long as they get paid the heaps they do. And secondly burner is former electrician and Jet whatever by education and trade, they simply totally lack the education to understand higly complex dynamics and fysics and thus they most likely haven't give a second thought to the trueness pf evaluation and even if they have the above reason applies, attleast publically.

For example practically none of the Indy/CART drivers can comprehend the complexity of the stress analysis, aerodynamics and uneven gasdynamics involved in creating competetive vehicle for them.

Equally I'm pretty sure that most pros have enough to worry about in their own practise and developement rather than the gun as long as it goes bang, the bullets land where aimed and load/gun meets the rules. (yeah yeah fits hand etc. etc. the usual things)

If the departments of ordnance had been listening to gun "gurus"(=old fat gitts) around the world, the infantry battles would be still fought with "good old rugged and reliable weaponry" like single shot rifles, since "a repeater rifle will only lure troopers to waste their ammo".

At the point when any society involved in any technological interest throws the anchor and refuses to develope since a "guru" says something theres something seriously going wrong.
Analogue to point succesfulness of anti guruism and scientfic aproach is Glock gmbh, what I know Gaston Glock had never fired a weapon before the project. How large percentage of US LEOs use glocks these days?

Even if the "founding fathers of ipsc" had to set the PF evaluation the way it is because of lack of chronys and calculators (and not because of social interest in "Man's guns" and economical connections in modifying such ;). Why should we let that keep us down, at the days that only place one sees a ballistic pendulum is museum.

And finally if energy doesn't work terminally in real world, I'd like too see the dude too that stands next to PF=0 stationary device, derivated from one german jewish egghead fysicist's thoughts shuch as E=mc^2 :)
The lad really isn't hurten when he turns into plasma, since it's only energy and no momentum ended up to him before total disintergration.

"In the future I will understand better"
Gattling = ;)
 
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