Quantitative Ammunition Selection and what it's all about. Lengthy post!

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K-Texas
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Quantitative Ammunition Selection and what it's all about. Lengthy post!

#1

Post by K-Texas » Sun Oct 20, 2019 6:08 pm

Hopefully, some of you are familiar with the book written by Charles Schwartz. Due to some articles and forum posts from the past, Charles and I became acquainted about 5 years ago, IIRC.

This article is for everyone's benefit where I just happened to test a handload connected to other projects just after getting acquainted with Tnoutdoors9 some of you may be familiar with. This is not a handloading article. This is about ballistic testing that any shooter can do without the major investement for calibrated ordnance gel as the FBI uses. Regardless of advertising, other gel block products do not produce the same results which some of you may have read in articles elsewhere.

Tnoutdoors9 is a great guy, just as he appears to be in his YouTube videos/ He'd been looking in on the Western Powders blog and my buddy, Rob Behr, who edits the blog put us together. Tnoutdoors9 does not handload, and I don't do YouTube vids, but I have been a subscriber to his channel for a number of years now.

On Friday, I posted in this same section in the thread about .32 ACP vs .38 Snub revolvers. I mentioned that I would be doing some ammo testing later in the day with some of the loads being fired from a S&W 2 1/2” M66 that belongs to my Shooting Partner, or SP. I won't say unfortunately, but he waited until we were driving to the range before he told me about winning a raffle the day before at a local gun shop. For his $10 investment, he won a 4” S&W 686+ valued at and priced accordingly at $729! That definitely changed the gameplan. The chronographing we did with revolvers included a water test of the .357” 158 gr. XTP. Unfortunately, the stated velocity from the load data was well above what we chono'd from his new 686. I hadn't really decided how I would add this to the thread I mentioned, but more important facts evolved that I'd like to get into in familiarizing members with some things this member, with very few posts in nearly 2 years of membership, with some things I've mentioned before.

Most recently I've spoken about Momentum and how to find it in the scientific sense while some do no more than use Power Factor for gun games. I am not criticizing that at all. I can tell you that in the DPS testing for the pistol/caliber to replace the 4” 357 Magnums they'd been using probably longer than any other LE Agency. They did some study concerning recoil for a different DPS that they became vs what they had been with mostly male troopers. From the largest male to the smallest female troopers, they came to the conclusion that 160 Power Factor was the benchmark for all, even while the .357 SIG cartridges ran a bit higher with 125 gr. JHPs spec'd at 1350 FPS developing a Power Factor of 168.75. Now I'll mention the Momentum calculation again that gives results in Lb-seconds so you can see how they compare. I am very much into momentum when it comes to comparing defensive handgun rounds. And as mentioned in the other thread, Muzzle Energy can be easily extrapolated from the momentum calculation which is Mo = (BW / 225218) x Velocity. The formula includes the necessary calculation for mass (bullet weight in grains). For the 125 gr. .357 SIG load we're looking at 125/225218 x 1350 which equals .7493 Lb-seconds. To get Energy from that calc it's just a simple matter of multiplying Momentun x (velocity / 2). The loads I have the most confidence in achieve a minimum of .6500 Lb-seconds that might not be realistic for the smaller 9 x 19mm pistols like the S&W Shield or Ruger LCP. In those cases, or even for service pistols where for one reason or another a lower recoil has to be considered, or loss of velocity from short barrels, I put the minimum at .6000 Lb-seconds. In the other thread I mentioned some experimentation I've been doing and writing about concerning 147 gr JHP loads in 9mm, so I'll list values for 115, 124 and 147 gr bullets to reach .6000 Lb-seconds. With 115s that will be 1175 FPS. For 124s, 1090 FPS and with 147s, 919 FPS.

With pistols that small it's kind of obvious that Muzzle Energy will be hampered with 9 x 19mm pistols, and why I'm concentrating on them. You want to shoot a sub-compact chambered for a more potent cartridge? That is entirely up to the shooter and how much practice time they're willing to commit in mastering higher recoil.

I have to say that I agree with the DPS assessment of 160 PF which would yield 1280 FPS with a 125 gr. Bullet. Since the 124 gr weight is prevalent to the 9 x 19mm, factory loads will likely be rated +P+ and I've been working on such a load. 2 very important warnings here concerning safety. The length of my loads are not typical. I tend to buy 9mm pistols without chamber-length restrictions, and they are becoming fewer by the day. The test platform for the load we'll discuss is a Canik TP9sa with a 4.47” barrel. Longer loads can achieve the same velocity at lower pressure than shorter loads. Also, I've been doing this for 33+ years and I apply pressure testing techniques that are essentially mechanical determinators rather than actual piezoelectric PSI testing. I will not be posting my handload data as a result.

Now I'll mention 40+ years of handgunning. Along the way I've studied every concept I'm aware of concerning handgun cartridge effectiveness: some better than others. Charles Schwartz is retired from a Federal LE agency and happened to minor in physics before his LE career. Even with research that preceded my own experience; going all the way back to the Thompson LaGuard tests from the early 20th century, Charles has devised a calculation, successfully, for just about any theory that's been postulated. Some might seem exotic even, but the more common things more familiar to us, they are covered. Why would he go to such an extent? To prove his hypothesis that water testing can predict the penetration in FBI gel, which is the term I'll use going forward. Some of the gel products, I'm sure were created with the best intentions, but they simply do not yield the same results as FBI gel that even includes a specific temperature below 40 degrees. Last he told me, he was very near 900 data points from shooting into FBI gel and comparing the results to the same bullets fired into water. The rate of accuracy is above 95% in predicting penetration for FBI gel using his water testing techniques that I stray from a bit due to convenience. I've been shooting 1 gallon water-filled jugs for many years like many others except that I might not have been as exotic in terms adding barriers or packing newsprint into jugs. In his book, Charles recommends and uses large freezer storage baggies and provides all instructions.

Let me mention some things that also come with the penetration prediction. Wound mass and volume and predicting percentage of stops based on successive hits. Charles rates a 1st shot above 70% to be very good. By the third shot the better loads will rank above 98% and usually above 99% for the 4th shot which is the practical limit considering how many shots would be required to achieve 100%, which with calculators can go almost to infinity. One key prediction is for the energy expended in the 1st to 15th centimeter of penetration. My own theory has taken that a bit further when the Q-Models since calculating power in kiloWatts. I certainly don't want anyone to confuse that with the misnomer of Hydrostatic Shock. What I've been seeing is that power values increase with higher levels of the factor ∆E15 which is energy displaced in the 1st to 15th centimeter. I've been calling that Rapidity of Expansion. If you put value on Ballistic Pressure Waves, or BPW, and I do, that is also calculated.

There is no theory that I have shunned. I take them all into consideration. I've been hoping to see Charles release the Q-Model spreadsheet program commercially. I've gone from the 1st to the current edition where he added a few elements that have had me calling the current edition, 4.1.3.

This load I used was a 124 gr. HST handload, and they're not typically available to the handloader. They were “pulled” bullets from RMR. The Underwoods load chrono's at 1299 FPS from a Glock G19 which compares very well to their spec of 1300 FPS, and as mentioned, the load is rated +P+. We'll save all that for another discussion, but I'll just say that before buying the Canik TP9sa I contacted Century Arms to be assured that the pistol was indeed +P rated before I ordered it sight unseen. Friday was the first trial of that handload that chrono'd 1281 FPS, but I viewed several ejected cases to find no signs of excessive pressure. The recovered average diameter measuring at 6 points, 3 for outside dia of the petals and 3 between the petals is .5762”. I was very gratified to see that the 124 gr HST was up to the challenge of 1281 FPS.

So let's get to the numbers. That load has a power factor of 158.8. Momentum is .7053 Lb-seconds while muzzle energy is 452 Ft/lbs. Retained weight is 122.8 grs. Now predictions from the Q-Model. The prediction for penetration is 13.44”. Wound mass is 1.7259 oz. Wound Volume is 2.8709 cubic inches. The value for ∆E15 is 313.07 Ft'lbs Power in kW is 162.09 with a Ballist Pressure Wave value of 729.318. Prediction for successive shots is 1. .7498; 2. .9374 with the 3rd at .9843.

Sorry about the thread length, but I hope you find the information useful. I have just worked myself up to the pre-game Cowboys vs Eagles!;-)
Last edited by K-Texas on Mon Oct 21, 2019 6:09 pm, edited 1 time in total.
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K-Texas
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Re: Quantitative Ammunition Selection and what it's all about. Lengthy post!

#2

Post by K-Texas » Mon Oct 21, 2019 12:53 pm

Questions and comments are welcome. ;-)
Anything that can be corrupted by man; will be corrupted.

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K-Texas
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Re: Quantitative Ammunition Selection and what it's all about. Lengthy post!

#3

Post by K-Texas » Mon Oct 21, 2019 2:15 pm

For those interested in higher velocity 9mm 124 & 147 gr. loads you can find info here: http://blog.westernpowders.com/ ;-)
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K-Texas
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Re: Quantitative Ammunition Selection and what it's all about. Lengthy post!

#4

Post by K-Texas » Wed Oct 23, 2019 9:11 pm

Okay, so call me a heretic for bumping this thread in hopes that it can be seen by as many readers as possible.

Or, consider the handload I used as an example earlier. I knew that Charles Schwartz would like it, so I sent him the data I posted herein. I heard back from him on Monday with the reaction I was pleased with. I mentioned the value for energy expended in the 1st - 15th centimeter. Since he wrote the math and checked mine before I had used his Q-Model program, myself, he was very enthusiastic about that value: the energy departed that is higher than some 9mm loads, or others have at the muzzle.

Please believe that my interest is in seeing that others get the knowledge. I know of none better, and the simplicity for conducting the test for yourselves is there for the taking.

About the time, or shortly after, when I registered here as a member, I had pretty much decided that trying to get the knowledge to those willing to comprehend it was a futile endeavor. I mentioned my 33+ years of experience in handloading, and even more in terms of study because I was self-taught. It was just me and my load manuals back in 1986. My particular occupation certainly helped: there was no internet, nor mentor.

Nonetheless, since about 15 years ago when I first became a member of any gun forum, this has become a quest that some might consider pay-it-forward. And as such, I don't believe that anyone could look back over my entire experience and see me using the term, NOO-B, Newbie, or anything like that. The last thing I'd want to do is to appear to want to over-complicate these things.

Please do not be intimidated from anything I post! It's just a case of firmly believing that, as of now, there isn't any better ballistic science I'm aware of. And, circumstances brought about many questions after the tragedy commonly known as, "The Miami Shootout of 1986." I do however believe that is relevant to anyone choosing to protect lives with a handgun. The outcome that I hope to see before I give up posting publicly, is that others will investigate. I don't want to take credit where credit is not due, but I believe we're getting closer to seeing Charles make his spreadsheet available commercially.

So please engage! I'm a Texan just like the rest of you. I live in what is commonly called here as, The Heart of Texas, but I grew up in Houston. Heart of Texas is easier than saying North West Central Texas, LOL! South, southwest of us about 45 miles away, the town of Brady claims to be the geometric center of Texas, and that's okay to. By latitude and longitude, I think they'd both need to be considered for a resolution. Point being, I love Texas. I loved growing up in Houston while Galveston was so near by. I've been in the same house for almost 25 years now, and after having traveled through the entire state, I can't think of any part of the state I'd rather be in. I've been through a couple of tornadoes. The first while I was in elementary school where the residence 4 houses down had it's garage picked up and sat atop the garage next door. In 2007, one passed very close here, caused no damage until about 3 blocks East and uprooted a tree. Like the movie, if you've seen it, The World According to Garp, I like our odds right where we're at. My daughter was born in Sweetwater where I've also lived and met my wife, born and raised in Abilene. Somewhere else we spent a good number of years.

So if there are no questions, here, or in some of the reloading threads I've started, this will be the last post here, otherwise. The thread seems to have received a good amount of coverage in terms of the number of viewers. If you have questions where you might feel any amount of trepidation in asking, feel free to PM. ;-)
Anything that can be corrupted by man; will be corrupted.

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Re: Quantitative Ammunition Selection and what it's all about. Lengthy post!

#5

Post by DocV » Wed Oct 23, 2019 11:45 pm

Thanks for your very interesting posts. As a duffer loader there is no way that I understand all the complexities of reloading. I was reading and digesting your recent 9mm post as, for some reason, my pursuit for an accurate 9mm load has proven to be fruitless. I recently purchased some RMR 124 Truncated Cone projectiles but pushed them over to the side of the loading room while I mulled over a plan for my next charge my 9mm accuracy hill. I noticed you used Silhouette for your 124 grain loads and have been pleased with that powder so I might spring for some more Silhouette for my 124 9mm loads. Silhouette was not my favorite powder for 147 LRN though, so I had been considering other powders that I have on hand - some VV 320, Bullseye, and some newly acquired, but untested, Sport Pistol. Anyway, I do enjoy your posts but, as you can tell, I'm a slow learner.
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K-Texas
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Re: Quantitative Ammunition Selection and what it's all about. Lengthy post!

#6

Post by K-Texas » Thu Oct 24, 2019 3:03 pm

Thanks for the reply, DocV. I do tend to use Silhouette the most for 124 gr JHP defense loads but True Blue is another good one if I'm chasing accuracy with excellent uniformity as measured by extreme spread and standard deviation.

As luck would have it, I've done some testing with the "in-house" RMR 124 gr. JHP. In the past we found the same weight bullet from Nosler to be very accurate, but I just couldn't get them to expand much, even above 1200 FPS. I think they'd be great for .38 Super and .357 SIG. The RMR 124 gr JHP is very similar in profile and is proving quite accurate. I have found that they are capable of up tp 1180 FPS without separating. Pretty good for a cup and core JHP.

For competition shooters, I did investigate an accuracy load with the RMR 124 gr JHP to reach 130 PF to have a bit to spare over the 125 PF minimum. Most folks are using 147 gr bullets to do that for softer perceived recoil. Not sure I could tell the difference, so I thought I might offer an alternate for gun games. And, I had Accurate No 2 that I wanted to try for that. 4.2 grs seems to be the magic number for my loads with 4.3 grs tested; not showing any improvement. I have to note, however, that my OACL is 1.122"/28.5mm. That's pretty long due to the shorter ogive of the RMR 124 gr JHP where Nosler loaded theirs to 1.120" and is very similar in shape. Nosler found best accuracy with True Blue which may be my overall favorite handgun powder, but I felt that No 2 would have even lower recoil. It has not been at all unusual for the 4.2 gr No 2 load to give standard deviations of around 3 FPS. Very soft shooting and quite accurate.

Sorry to drift because QAS is about bullet effectiveness and penetration predictions. I use handloads most of the time whereas the actual testing done by Charles Schwartz is done with factory loaded defense ammo, including some of the best loads available. You do not have to be a handloader, but you will need a velocity measurement for the statistics. If you're really serious about your defense loads, good chronographs can be bought at around $100 if you don't know someone who can chrono loads for you.;-)
Anything that can be corrupted by man; will be corrupted.

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

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