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Old January 2, 2013, 06:03 PM   #35
481
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Join Date: April 18, 2011
Posts: 486
Quote:
Originally Posted by zombietactics:
It should be noted that this method has not been verified by (or even submitted to, last I heard) a single peer-reviewed journal of physics or metrology. Schwartz' book is self-published, and therefore doesn't have the authoritative weight of something reviewed and edited by a publisher of scientific works.

It may be 100% accurate, or it may be just the latest in a long line of "fad physics" testing methods, which later turn out to be hokkum dressed up in numbers. I make no claim one way or the other, just to be clear. Schwartz' qualifications seem pretty consistent with at least having a clue, so it's a perspective worth consideration.

Even so, unproven methodologies should be viewed as "interesting perspectives" until such time as their claims have independent verification from qualified, disinterested parties.
According to the website, it appears to have been vetted by a munitions engineer- that's a heckuva lot better than all of the anonymous crap and opinions that I've seen on the 'net over the years.

I know that there are those who will 'poo-poo' the munitions engineer's statement, but run against actual testing in gelatin that our department conducted about seven years ago when they were researching replacement issue ammo, I have been amazed at just how close this model comes to matching that data. The other model that I use occasionally, by MacPherson, is also a self-published work and fits quite well with the data that I have compared it against.

Much like the old platitude, "Money talks, B.S. walks", the proof of both models' accuracy/validity is how well they work in the real world against real gelatin data- not how they were printed.

By way of example, I've compared the Schwartz bullet penetration model's prediction against a couple of well-known examples that I am sure most folks here on TFL have seen before:


Example #1:

This .45ACP 230 gr FMJRN @ 869 fps has a total penetration depth of about 65cm or 25.6 inches:


The Schwartz bullet penetration model predicts a penetration depth of 25.7 inches.

Note: The MacPherson model predicts 30.4 inches of penetration.



Example #2

This 9mm 124 gr FMJRN @ 1189 fps has a total penetration depth of about 71-72cm or 28.3 inches if you "straighten out" the upward curve at the end of the bullet's path:


The Schwartz bullet penetration model predicts a penetration depth of 28.7 inches.

Note: The MacPherson model predicts 30.9 inches of penetration.


Quote:
Originally Posted by zombietactics:
I'd find it interesting to see a comparison between typical ball rounds used by the military ... NATO spec 124gr. 9mm @ ~1300fps vs. milspec 230gr .45ACP @ ~850fps
I'll be happy to do one for you if you want- just say the word.
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Last edited by 481; January 2, 2013 at 07:00 PM.
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