Screenshot of the QAS Q-Model

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K-Texas
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Screenshot of the QAS Q-Model

#1

Post by K-Texas » Tue Nov 19, 2019 4:26 pm

Charles Schwartz graciously granted me permission to post this screenshot of the Q-Model analysis of an experimental load I made with the 124 gr. HST to see if it is capable of matching the performance of the Underwoods 124 gr. +P+ Gold Dot load that TNoutdoors9 sent me for evaluation after firing them from overhead into a 50 gallon drum. He was not familiar with Quantitative Ammunition Selection at that time. At 1281 FPS, and a longer OACL than the ammo-makers can typically use, I did not feel it was necessary to push them to the slightly faster near 1300 FPS of the Underwoods load.

This is the load that I mentioned elsewhere that deposits as much energy into the 1st - 15th centimeter as some loads have at the muzzle.

I do not believe, based on the powder charge and OACL I used that this load would be above 38,500 PSI, the SAAMI limit for +P. For my own use, the loads will be lowered to 1250 FPS. This requires a very narrow window for powder selection as well as the longer OACL. DO NOT TRY THIS AT HOME! The load was made purely for experimental purposes. As you can see from the Q-Model data, it is extremely potent as far as 9 x 19mm ammo goes. Since it is at the high extreme of what can be achieved, and since Charles provided me with the screenshot, being very impressed by this level of performance, I thought I might show the data for what is possible. These type loads are certainly not for everyone. I'd even go so far as to say that if they interest you enough that you may want to order some, go ahead and order a heavier recoil spring as well, 2 - 3# heavier than your factory supplied recoil spring.;-)


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K-Texas
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Re: Screenshot of the QAS Q-Model

#2

Post by K-Texas » Tue Nov 19, 2019 8:58 pm

I'll help navigate the spreadsheet. The top left is where you enter the input data. Some variables related to JHPs are already entered. No changes needed until you change bullet types. Dropping down to diameter, you'll need to enter the average diameter. If you're checking a recovered JHP that petals into 6 segmants, you'll need the 3 outside diameters at their greatest points along with the 3 inner diameters between the petals. Add recovered mass and chronographed velocity and you're in business. I have loaded the 124 gr. HSTs (pulled) at different velocities. After a point where expansion is max, increased velocity will result in smaller expansion. As expansion decreases, depth of penetration will increase. Use barriers if you like. I play around with 4 layers of denim and I'm not sure there's a need to do that with a good performing JHP it will almost always decrease expansion slightly and increase penetration. The number I'm looking for without barriers is 12". So this particular load at 13.44" of penetration in the area just below your input data is quite good. Considering the other stats, that's probably a bit understated. Next to the penetration prediction are the predicted values for Wound Mass and Volume of the wound.

In the interest of brevity, I'll skip over to the data on the right side. At the top right is the value for Power in kiloWatts. This value has had much of my attention for a while now, but further examination will be needed. I know that I've run some pretty decent performing JHPs where it appears to me that 110 kW is a pretty decent minimum. This experimental load used is quite high at 162.09 kW and other data points reflect that like the very good penetration depth being above the 12" I want to see as minimum. The lower portion includes maybe one of the more valuable points represented with a triangle followed by E15. For short I call it deltaE15 unless I'm using a word program that provides the correct symbols. This value is for the amount of the bullets energy expended within the 1st - 15th centimeter. 313.07 is extremely high, Higher than what some 9mm loads have at the muzzle. That in combination with the excellent penetration accounts for the Power Value being as high as it is. My personal interpretation is that the high Power value is an indicator of how rapidly a JHP expands combined with the penetration prediction being adequate. P[I/H] is the incapacitation value for the first shot while incapacitation is defined as a thoracic hit with the event stopping in 30 seconds. To the right are the cumulative values where as you might imagine, they increase with each successive shot landed. Charles has always told me that really good performing loads typically come in at 70% for the first round. You can see the obvious increases with each successive round landed. The increased prediction above 70% for the first round is more significant than it may first appear. When by the 3rd round values will be above 98%. Those are the numbers I'm most interested in. Not much is left to the imagination at that point and a 4th round will have a value above 99%. I doubt that anyone is interested in seeing how long it takes to reach 100%. We're using computers, after all. I should also remind the reader that Charles Schwartz is a retired federal law enforcement officer. As far as the different theories go, I'd bet he's seen the vast majority of them. I'll also remind everyone that he's now at 900 tests where one JHP has been fired both into the FBI calibrated 10% ordnance gel in controlled temperatures, and into the water containers while the results agree at a probability above 95%. Anyone whose studied ballistics likely understands the significance of those results. I've never been a gelatin junkie and have been using vessels as simple as 1 gallon water jugs. QAS has better recommendations for that. But the fact is that the gel used by the FBI us not matched by any other. Yeah, you can buy some gel products on the cheap, just remember that water vessels are cheaper and most commonly available.

This really demonstrates the importance of shooting until the fight is over. No magic bullet or penetration theories. Opinions are great and all, so long as we remember that that's exactly what they are. Pure science is far better, and in this case Charles has covered every ballistic study I'm aware of that's been put into print with mathematical data provided since the early 20th century. Some better than others. Quite an extensive undertaking with what has been done in QAS. Understanding all of the parameters is best done by reading his book, Quantitative Ammunition Selection, available at Amazon and from the website. So far as my own mathematical abilities go, his formulations are solid and firmly planted into physical certainties. It's really been a great benefit in knowing that these things some of us have been doing at the range for many years, in my case, can be quantified.

The only omission I see here is that the latest Q-Model that I have also calculates the Ballistic Pressure Wave in PSI. Some consider that a bit controversial, but the fact is that if you implant transducers into a test animal, an oscilloscope can and does provide the magnitude of the pressure wave. The Dr.s Courtney are well known by some, but the fact is that the research has been going on for many years. Well before solid state electronics. I have personally wanted to see the Q-Model offered commercially and that is now in the works with a few more hurdles to leap. The best recommendation I can make is that if you'd like to have a copy of the Q-Model. let Charles hear from you. He's aware of what I'm posting here and will be looking in. ;-)
Anything that can be corrupted by man; will be corrupted.

The Lord is my shepherd; I shall not want . . .


flechero
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Re: Screenshot of the QAS Q-Model

#3

Post by flechero » Tue Nov 19, 2019 9:09 pm

Interested but I wasn't able to enlarge to pic so I couldn't read the data...


pushpullpete
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Re: Screenshot of the QAS Q-Model

#4

Post by pushpullpete » Tue Nov 19, 2019 9:35 pm

flechero wrote:
Tue Nov 19, 2019 9:09 pm
Interested but I wasn't able to enlarge to pic so I couldn't read the data...
Try enlarging the text size several sizes. I push and hold down CTRL, while tapping +/= . On my computer, this makes the
pictures easier to see for my old eyes. To make it smaller, push and hold CTRL, while tapping _/- . YMMV

:txflag: :patriot:


Topic author
K-Texas
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Posts in topic: 3
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Joined: Wed Dec 20, 2017 2:34 pm
Location: Heart of Texas

Re: Screenshot of the QAS Q-Model

#5

Post by K-Texas » Wed Nov 20, 2019 2:06 pm

pushpullpete wrote:
Tue Nov 19, 2019 9:35 pm
flechero wrote:
Tue Nov 19, 2019 9:09 pm
Interested but I wasn't able to enlarge to pic so I couldn't read the data...
Try enlarging the text size several sizes. I push and hold down CTRL, while tapping +/= . On my computer, this makes the
pictures easier to see for my old eyes. To make it smaller, push and hold CTRL, while tapping _/- . YMMV

:txflag: :patriot:
Thanks for your assistance! ;-)
Anything that can be corrupted by man; will be corrupted.

The Lord is my shepherd; I shall not want . . .


pushpullpete
Senior Member
Posts in topic: 2
Posts: 340
Joined: Sun May 10, 2015 3:44 pm

Re: Screenshot of the QAS Q-Model

#6

Post by pushpullpete » Thu Nov 21, 2019 8:53 pm

K-Texas wrote:
Wed Nov 20, 2019 2:06 pm
pushpullpete wrote:
Tue Nov 19, 2019 9:35 pm
flechero wrote:
Tue Nov 19, 2019 9:09 pm
Interested but I wasn't able to enlarge to pic so I couldn't read the data...
Try enlarging the text size several sizes. I push and hold down CTRL, while tapping +/= . On my computer, this makes the
pictures easier to see for my old eyes. To make it smaller, push and hold CTRL, while tapping _/- . YMMV

:txflag: :patriot:
Thanks for your assistance! ;-)
:tiphat:
:txflag: :patriot:

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