DeepSouth
Random Guy
On page 6 of the report it says "Shot 2 (Unmodified Bullet)" that is what had me thinking it was not a HC. If none of the tested bullets were standard what would we have to compare them with? Surely one of them was standard.
New bullet: "hypercav"
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On page 6 of the report it says "Shot 2 (Unmodified Bullet)" that is what had me thinking it was not a HC. If none of the tested bullets were standard what would we have to compare them with? Surely one of them was standard.
waldonbuddy
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Has anyone who answered the questionnaire, gotten "what they wished for"?
http://www.hypercavbullets.com/wish.htm
http://www.hypercavbullets.com/wish.htm
Seriously, don't delete THIS post, eh? - a real test would be to take some bullets and drill the holes all the way through, and some with the holes drilled ALMOST all the way through to the hollow point cavity. Both would have the same structural compromise to the jacket (which is the only effect I believe we've seen), but only the ones with the holes drilled all the way should have the so-called "hyperCav" effect. If ANY difference you may be seeing in such a small sample is really due to the proposed venting of air from the cavity, as was the original claim, then the ones with the holes all the way through should show the proposed benefit in performance. A sample of more than 1-2 would be nice, but you are relying on generous, independent testers.
They1
Member
Shot #2 was the control round.
They1
Member
KS Deputy,
The photo page works, there's just nothing posted yet. Right now, we've been concentrating on the facts and results of testing, rather than some photos that I doubt would be anything more than dressing.
I'd prefer at this time to focus on the steak, instead of the sizzle.
DeepSouth
Random Guy
They1
Member
DS, I did now, sorry I missed it...
Please note that the entire point of porting ANY bullet, regardless of brand or caliber, is to increase RELIABILITY of those rounds...to offer a greater chance of that bullet expanding, as designed, over a wider range of in-field conditions. Any bullet, no matter how well designed will not open if it does not reach critical-mass. Energy is always lost as the cavity tries to pressurize with tissue material.
Porting only adds to the effeciency of that process.
All of these test results are by-products of that process. What was most important to show, is that porting not only causes the round to expand, but that there is no significant loss of performance in the process.
It just happens that the porting has some other effects that to date, are "interesting".
A more energetic expansion translates to a more damaging wound cavity.
They1
Member
Hc website update:
FYI: We've updated the website 'Photo Gallery' to show some additional test results, and on the 'Marketing Page' (scroll down) includes a video of a water jug test.
(*You'll note the impact force difference of the HC round, vs. the control)
http://www.hypercavbullets.com
More test results are pending, and I'll post them as they become available.
FYI: We've updated the website 'Photo Gallery' to show some additional test results, and on the 'Marketing Page' (scroll down) includes a video of a water jug test.
(*You'll note the impact force difference of the HC round, vs. the control)
http://www.hypercavbullets.com
More test results are pending, and I'll post them as they become available.
I found a few inconsistencies in the equations and verbiage on your technology page.
1. The equation for stagnation pressure of water shows p as density of water and v as velocity of the fluid with respect to the bullet. v is then established as 243.84 m/s, and plugged into the equation. But when it's plugged into the equation, it turns into (259.08 m/s^2)^2. Different number, incorrect unit (acceleration instead of velocity). I didn't crunch the numbers, but the inputs and units definitely don't line up.
2. When calculating work, the statement is made: "The change in volume is calculated by assuming it will be isentropic compression (no heat transfer in or out, aka instantaneous)".
No heat transfer would be an adiabatic process, not isentropic.
Anyway, I'm not a PhD but I have worked some thermodynamics & dynamics equations. If I'm wrong that's fine, I just hate to see errors on an entrepreneur's website.
Cheers
1. The equation for stagnation pressure of water shows p as density of water and v as velocity of the fluid with respect to the bullet. v is then established as 243.84 m/s, and plugged into the equation. But when it's plugged into the equation, it turns into (259.08 m/s^2)^2. Different number, incorrect unit (acceleration instead of velocity). I didn't crunch the numbers, but the inputs and units definitely don't line up.
2. When calculating work, the statement is made: "The change in volume is calculated by assuming it will be isentropic compression (no heat transfer in or out, aka instantaneous)".
No heat transfer would be an adiabatic process, not isentropic.
Anyway, I'm not a PhD but I have worked some thermodynamics & dynamics equations. If I'm wrong that's fine, I just hate to see errors on an entrepreneur's website.
Cheers
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DeepSouth
Random Guy
I hate to say it but at this point I see no real advantage to a HC bullet over a quality JHP. It is possible the HC bullet is causing a higher chance of the bullet expanding, but I think hundreds more rounds should be tested because at this point I see little difference. IE: I have not seen a test that showed a "Standard" hp that didn't expand when a HC that did.
Sorry, but your loosing me. It started with the Pics in post #204, the "Unmodified" bullet seemed to have better all around expansion.
Sorry, but your loosing me. It started with the Pics in post #204, the "Unmodified" bullet seemed to have better all around expansion.
They1
Member
They1
Member
I agree. You don't get to prove 'reliability' with only a few rounds.
Hundreds are being tested by some manufacturers and some reviewers as well as here.
Having said that, considering the grave nature of firing in self-defense, and considering that your life may depend on just one bullet, I think even one bullet that fails to open is one too many...
If Hypercav is a low-cost addition to any existing bullet AND it has the potential to make that "critical difference", why wouldn't you want every advantage possible?
Nobody I've talked to has suggested adding ports to an existing bullet will have a significant effect on cost, so why not?
They1
Member
I passed your observations on to my PhD guy. he asked me to post his reply:
"He is right on the unit typo (though the arithmetic is correct, I just had
a typo on the MS Word formula, not the excel sheet I used for
calculations, I went back and checked).
However, an isentropic process is a reversible adiabatic process, so he
was right that it should be an adiabatic process, but I also considered it
reversible (like a frictionless, massless air piston with perfectly
insulated walls) which would make it isentropic.
You should post this and let him know he's right about the typo in the
equation, and half right about the other thing, and that the typo is going
to be fixed on the website."
*I'm glad you caught that! Thank you.
-They
Yeah, I understand about the reversibility aspect making it possible to model as isentropic. You could just as easily pull the bullet out of the water and uncompress. I just figured that if you guys were going to take the time to post all the equations and all the assumptions, that you'd want to be as specific and accurate as possible.
With the information provided - "The change in volume is calculated by assuming it will be isentropic compression (no heat transfer in or out, aka instantaneous):" - the only assumption stated was that the process had no heat transfer, not that is was reversible. I understand I'm nitpicking a little, but since the information is posted on the world stage, I believe every word matters!
Going back to the stagnation pressure issue, the following statement was made - "Then the stagnation pressure at 800 fps (243.84 m/s) is..." - The equation was then posted and numbers inputted. In the final equation, the number changed from the 243.84 m/s posted there to 259.08 m/s. Was that intentional, or was one of the two numbers a typo?
Thanks for considering my comments.
With the information provided - "The change in volume is calculated by assuming it will be isentropic compression (no heat transfer in or out, aka instantaneous):" - the only assumption stated was that the process had no heat transfer, not that is was reversible. I understand I'm nitpicking a little, but since the information is posted on the world stage, I believe every word matters!
Going back to the stagnation pressure issue, the following statement was made - "Then the stagnation pressure at 800 fps (243.84 m/s) is..." - The equation was then posted and numbers inputted. In the final equation, the number changed from the 243.84 m/s posted there to 259.08 m/s. Was that intentional, or was one of the two numbers a typo?
Thanks for considering my comments.
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They1
Member
HOV,Yeah, I understand about the reversibility aspect making it possible to model as isentropic. You could just as easily pull the bullet out of the water and uncompress. I just figured that if you guys were going to take the time to post all the equations and all the assumptions, that you'd want to be as specific and accurate as possible.
With the information provided - "The change in volume is calculated by assuming it will be isentropic compression (no heat transfer in or out, aka instantaneous):" - the only assumption stated was that the process had no heat transfer, not that is was reversible. I understand I'm nitpicking a little, but since the information is posted on the world stage, I believe every word matters!
Going back to the stagnation pressure issue, the following statement was made - "Then the stagnation pressure at 800 fps (243.84 m/s) is..." - The equation was then posted and numbers inputted. In the final equation, the number changed from the 243.84 m/s posted there to 259.08 m/s. Was that intentional, or was one of the two numbers a typo?
Thanks for considering my comments.
I want to answer your questions in the detail it deserves. However, given the highly technical nature of the subject-set, and out of respect to those who would not find this context of interest, if you would PM me with your questions/thoughts, I'd be happy to respond accordingly. Thank you.
They1
Member
New Test Results
New test to report:
Magtech .45+P 165gr Copper (SCHP)
http://www.youtube.com/watch?v=1b0bK9xmxPs
The following are comments by tester:
*Analysis and discussion on the results: (Isaiah Kellogg-PhD)
First and foremost, the Magtech SCHP doesn't appear to work well at all. Only 1 out of 4 of the factory bullets expanded - and that's in water! Water tends to induce a bit more expansion than ballistic gelatin does. But even with water, the Magtech factory SCHP only manages to expand 25% of the time. Not very good odds.
The purpose of HyperCav was to increase the reliability of expansion of a hollowpoint bullet. In this case, we see that very well. The HyperCav modification about doubled the probability of expansion.
That wasn't particularly unexpected. What was unexpected, is that the impact of the HyperCav bullets was significantly more violent than the factory bullets - even when they didn't expand! Why is that?
For a simplified demonstration, go into your bathroom, and turn on the cold water, full blast. Then, with one quick motion, slam the valve closed all the way. You might hear a bang and then your pipes rattling. That's called "water hammer."
Water is an incompressible fluid, which means that the volume of water can't change (well, there are minor volume changes with temperature, but squeezing water can't compress it). When you turn on your faucet, all the water in the pipe is moving. When you shut off the faucet, the water suddenly stops. All that kinetic energy has to go somewhere - it turns into pressure.
In fluid dynamics, pressure and kinetic energy are interchangeable. A rocket turns pressure into kinetic energy by using a nozzle. An object flying through a fluid causes kinetic energy to turn into pressure where the fluid hits the front of the object, that pressure is known as drag.
So in your water pipes, suddenly turning all that kinetic energy into pressure isn't a good thing. The fix for that is to install a small vertical section of capped pipe near the faucet. This vertical pipe, maybe six inches long, is full of air. When the faucet is suddenly turned off, the sudden pressure increase is cushioned by compressing that air.
Where else have we seen an air cushion?
That's right, in the cavity of a typical hollowpoint bullet. Remove that air cushion and what happens when something suddenly increases the pressure of the water?*
Gelatin tests using Federal .40 HST pending.
New test to report:
Magtech .45+P 165gr Copper (SCHP)
http://www.youtube.com/watch?v=1b0bK9xmxPs
The following are comments by tester:
*Analysis and discussion on the results: (Isaiah Kellogg-PhD)
First and foremost, the Magtech SCHP doesn't appear to work well at all. Only 1 out of 4 of the factory bullets expanded - and that's in water! Water tends to induce a bit more expansion than ballistic gelatin does. But even with water, the Magtech factory SCHP only manages to expand 25% of the time. Not very good odds.
The purpose of HyperCav was to increase the reliability of expansion of a hollowpoint bullet. In this case, we see that very well. The HyperCav modification about doubled the probability of expansion.
That wasn't particularly unexpected. What was unexpected, is that the impact of the HyperCav bullets was significantly more violent than the factory bullets - even when they didn't expand! Why is that?
For a simplified demonstration, go into your bathroom, and turn on the cold water, full blast. Then, with one quick motion, slam the valve closed all the way. You might hear a bang and then your pipes rattling. That's called "water hammer."
Water is an incompressible fluid, which means that the volume of water can't change (well, there are minor volume changes with temperature, but squeezing water can't compress it). When you turn on your faucet, all the water in the pipe is moving. When you shut off the faucet, the water suddenly stops. All that kinetic energy has to go somewhere - it turns into pressure.
In fluid dynamics, pressure and kinetic energy are interchangeable. A rocket turns pressure into kinetic energy by using a nozzle. An object flying through a fluid causes kinetic energy to turn into pressure where the fluid hits the front of the object, that pressure is known as drag.
So in your water pipes, suddenly turning all that kinetic energy into pressure isn't a good thing. The fix for that is to install a small vertical section of capped pipe near the faucet. This vertical pipe, maybe six inches long, is full of air. When the faucet is suddenly turned off, the sudden pressure increase is cushioned by compressing that air.
Where else have we seen an air cushion?
That's right, in the cavity of a typical hollowpoint bullet. Remove that air cushion and what happens when something suddenly increases the pressure of the water?*
Gelatin tests using Federal .40 HST pending.
They1
Member
That's a great thought!
As this projects has developed, of course we've been thinking about the "what if's".
From the testing, we've seen a much more energetic reaction from the hydraulic water hammer effect. One of those interesting surprises that is often found in any R&D project.
Question is, what do we do with this entity?
In the long term, we have theorized that as the Hypercav concept "matures", that basic bullet designs will evolve, or be made to optimize the ported concept and function.
One of those could very-well be a bullet specifically designed not to expand, and/or have larger ports. This could, in theory, enhance the hydraulic effect, making for a pretty vicious penetrator round.
Of course, the walls of such a round would have to be heavily modified to resist cracking. There is a ton of energy being exchanged...
We're working up some 30-30 rounds. We'll see what those do. Stay tuned...
They1
Member
Sweet! You really got my attention! :mrgreen:
They1
Member
You're right, it was a .357.
As things unfold, there will be a broad spectrum of bullets to be tested.
Porting is a brand new entity, so there is a lot of experimenting to do.
However, to be specific to Hydra Shok, I'm kinda hesitant to fool around with these rounds considering when I was at SHOT Show, I had a Federal Rep tell me personally the the HydraShok was a "gimmick".
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