kinetic pulse

[huntsman]

In browsing the internet, I ran across the following website that contains some very interesting and eye-opening physics research in the area of bullet performance. I downloaded the kp chart for future reference. The conclusions about bullet interaction with media helps dispel some of the false notions I had (and I'm sure many more have) about bullet energy and performance on game.

The scientific jargon gets a bit thick, but if you can follow it there is a very important concept (kp, or kinetic pulse) about bullet performance that is well-documented by the research findings. I will be including kp in my future considerations of calibers, cartridges, and load data from now on.

Most interesting is how neither energy nor momentum alone indicates the exact performance of a bullet upon impact! This has long been a debate among firearms purists. I think that the concept of kp will at least advance our understanding of the physics of this important concept, if not lead to a whole new way of analyzing ballistic performance.

I wouldn't be surprised if kp replaces ft/lbs as the theoretical measure of a load's potential game-stopping power in the near future. It surely helps explain the great field performance of some of the seemingly tame "on paper" calibers that have long been favorites of many shooters, such as the 6.5x55SE, 7x57, and 7mm-08, just to name three off-hand.

Give this wedsite a visit; you won't be disappointed  :grin: : http://www.xmission.com/~fractil/math/kp.html

[april]

Thanks for the link... Kinetic pulse is very interesting.

[Black Jaque Janaviac]

Uggh!

I like the idea.  It appears that kinetic pulse could be very useful.

Unfortunately, kinetic pulse will not get anywhere unless someone other than that author decides to pick it up and flesh it out.  

That was one miserable piece of writing.  Don't feel stupid if you are getting "lost" in the technical mumbo-jumbo.  It really isn't that bad.  What is getting you lost is the writing style and technique.  Just awful.

Rather than ripping it apart anymore than what I've done.  I will add some thoughts for where this needs to go.

The kinetic pulse, simply the product of momentum and kinetic energy follows common sense and intuition very nicely.  It basically describes what experience has already taught us.  That bullet weight does matter, and so does velocity.

However, the biggest problem it had was the neglect of terminal performance.  Based on KP alone, there is no difference between full metal jackets and soft points.  Accept to say that the soft point runs the risk of fragmenting and therefore reducing the KP.   But what if the soft point performs ideally?

I think in much of his discussion on penetration he uses mass when sectional density would be a better description.  We all know that a 200 grain .45 bullet will penetrate differently than a 200 grain .30 bullet.  Even if velocities and construction are the same.

So kinetic pulse has a lot of merit, it just needs a lot of work before the shooting public will embrace it.

[Mikey]

Geez guys, don't get me wrong but I always thought a pulse was something men our age looked for in a girlfriend..... :-D .  Sorry, just Mikey here.

[huntsman]

BJJ,

Certainly I agree with you journalistic assessment. The style is more of a scientific report, but even at that rather ragged. The nuances of kp are indeed yet to be fleshed out. The author conceded that he was disregarding bullet shape and diameter from the onset, so we know that there is more to the story than JUST kp. He did do some extensive work with various bullet types in soft clay to measure bullet performance. Did you miss that? It IS easy to miss something in that rambling scientific diatribe.

No, it's not by any means a comprehensive work, and definitely not ready for prime time, so to speak. But I do think the essence of the work has a lot of merit in terms of getting us beyond ft/lbs and velocity as our end ballistic performance statistics. To me its kind of like the first brick in a new construction; you aren't going to build a house with it, but its a good start. Anyway, I'm glad you tuned in and got something out of it.

[Black Jaque Janaviac]

Huntsman,

I agree, KP has merit, as does it's counterpart E/M.  

Actually if you take the three, KE, KP, and E/M and look at each of those in relation to each other you get better indicators of bullet/load performance/use than any one by itself.

[huntsman]

BJJ,

Sounds like an idea for a new formula! Maybe you ought to post that as feedback on the website. I think the author might be interested.