Thank you.....I try to be practical, factual, and evidence based in my pursuits.
Thank you.....I try to be practical, factual, and evidence based in my pursuits.
Facts matter...Feelings Can Lie
''Politics is for the present, but an equation is for eternity.'' ―Albert Einstein
Full disclosure per the Pistol-Forum CoC: I am the author of Quantitative Ammunition Selection.
Here's one of Andrew's latest--posted March 1st.
Does this signal a return to organic gel? Curious about what medium he choses in the future.
Sorry for the thread drift since this isn't 147 9mm related.
Last edited by Tokarev; 03-01-2019 at 03:35 PM.
I sure hope so. Perhaps this is a harbinger of things to come?
Nonetheless, an interesting and informative test. Thanks for posting it.
I did notice that there seems to be no BBs present in the test block he uses in the video which surprises me given Andrew's usual inclusion of that data (BB validation, penetration depth, velocity) in his test results.
Perhaps I am too prone to the picking of nits, but when I see what I hope are 'legitimate' tests conducted in 'real' 10% concentration porcine-derived ordnance gelatin, as I have become accustomed to seeing in his tests, and have come to expect to see at least four distinct elements, so that the results can be assessed in a reasonable manner;
1.) BB validation values (velocity, penetration, temperature, etc.)
2.) the presence of some sort of scalar reference along the 'expected' shot line (ruler, tape measure, etc.)
3.) some sensible representation of the test data (e.g.: average bullet expansion diameter, initial/retained mass, impact velocity, maximum penetration depth)
4.) In situ imagery of the test projectile in its position of rest at its maximum penetration depth as well as the entirety of the projectile's path along with the scalar reference, preferably from at least two different sides of the test block(s)
Typically, he meets most of these requirements under his ''The Chopping Block'' account, but since this is under the arfcom banner maybe they didn't specify anything so strict?
The other reason that I enjoy Andrew's testing (in 10% ordnance gelatin, that is) so much is that his test data typically 'confirms' well against the penetration models found in QAS.
In this case, his test data...
Max. Diameter: 0.769''
Min. Diameter: 0.517''
Avg. Diameter: 0.643''
Initial/Retained Mass: 125 gr./110.7 gr.
Avg. Impact Velocity: 2,493 fps
Penetration Depth: 15.4''
...when run through the Q-model, gives predicted penetration depths of:
15.07'' (using the bullet's initial mass)
13.35'' (using the bullet's retained mass)
...and when run through the mTHOR model, gives predicted penetration depths of:
17.94'' (using the bullet's initial mass)
15.89'' (using the bullet's retained mass)
Incidentally, when Andrew's test data is run through Duncan MacPherson's penetration model, the following predicted penetration depths result:
14.22'' (using the bullet's initial mass, which includes +2'' 'correction-value' for neck length)
12.83'' (using the bullet's retained mass, which includes +2'' 'correction-value' for neck length)
I hope that this is the beginning of many more such tests to come.
Last edited by the Schwartz; 03-02-2019 at 03:54 PM.
''Politics is for the present, but an equation is for eternity.'' ―Albert Einstein
Full disclosure per the Pistol-Forum CoC: I am the author of Quantitative Ammunition Selection.
Ok so I'm confused.
Should we all just ignore clear gel tests if we're serious about choosing good defensive ammo?
If thats the case, is there a resource on the internet that has extensive tests on different loads we can see and that is worth our consideration?
To paraphrase Dr. Roberts here―
―''anything worth doing, is worth doing right''.
On page 1 (see posts #16 and #17) of this thread, Dr. Roberts confirms that no military or law-enforcement agencies are using Clear Ballistics Gel. There is a reason for that. Results obtained in Clear Ballistics Gel are comparable only with other data obtained in Clear Ballistics Gel. 10% ordnance gelatin, which has been researched and correlates strongly with porcine (thigh) muscle tissue which is/was used as a human tissue analog in terminal ballistic testing, is the current standard. Water can also be used as a test medium (with modified Poncelet penetration equations to predict maximum penetration depth), but it does not allow for the examination of temporary cavity effects.
As far as publicly available resources using correctly prepared 10% concentration ordnance gelatin to conduct such tests, they exist but they also are ''far and few between'' to the best of my knowledge.
One such example is Shawn Dodson's 'site, which is now committed to internet archival ''storage'' here:
http://web.archive.org/web/201201190...stactical.com/
Some of the cartridges tested in 10% gelatin are a bit dated; just a caveat.
Last edited by the Schwartz; 03-07-2019 at 04:57 PM.
''Politics is for the present, but an equation is for eternity.'' ―Albert Einstein
Full disclosure per the Pistol-Forum CoC: I am the author of Quantitative Ammunition Selection.
Is this http://brassfetcher.com/ a good place to find what I'm looking for?
I gotta admit, I'm less then a layman when it comes to the science behind this stuff, and as well have to admit, I'd been taken in by the clear gel tests.
The above "stickies" is likely the best available information on the interweb. Real testing needs to be done by somebody with experience ....... and it is likely quite spendy.
Sometimes I'm baffled by the questions people ask when the information is just a couple of threads up.
Brassfetcher (John Ervin, Mech. Eng.) does quite a bit of testing using 10% ordnance gelatin; but also in 20% ordnance gelatin (a common NATO/military test standard), so make sure that you know what you are looking at. John's work with 10% gelatin is thorough and one of the few sources that I rely upon when I require such testing. His testing (usually) relies upon multiple test shots for a specific munition; I've used his services to obtain some of the correlative data that I have used in my work.
Two such examples can be found here:
https://pistol-forum.com/showthread....l=1#post774644
https://pistol-forum.com/showthread....l=1#post774989
Ervin always provides the critical data as outlined below:
1.) BB validation values (velocity, BB penetration depth, temperature, test block time out of refrigeration, etc.)
2.) the visible presence of some sort of scalar reference along the 'expected' shot line (graduated ruler, tape measure, etc.)
3.) organized, sensible representation of the test data (e.g.: average bullet expansion diameter, initial/retained mass, impact velocity, maximum penetration depth)
4.) In situ imagery of the test projectile in its position of rest/orientation at its maximum penetration depth as well as the entirety of the projectile's path along with the scalar reference, preferably from at least two different sides of the test block(s)
Often, Ervin provides graphical data/tables relating to velocity and energy decay as a function of instantaneous time and/or penetration depth and lots of excellent high frame-rate videography that shows bullet yaw and temporary cavity effects.
In short, Ervin's production is 'first rate'.
Last edited by the Schwartz; 03-08-2019 at 11:01 AM.
''Politics is for the present, but an equation is for eternity.'' ―Albert Einstein
Full disclosure per the Pistol-Forum CoC: I am the author of Quantitative Ammunition Selection.
Thank you much, "The Schwartz".