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Lil-Rokslider
Highest sectional density wins.
Yeah it is always baffling when people say energy doesn't matter when you consider physics.How energy causes bullet expansion (based on well known real life science, not marketing materials):
Work-Energy Relationship
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How Work is related to Force:
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How Forces are related to stress:
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Stress-Strain relationship
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Yeah it is always baffling when people say energy doesn't matter when you consider physics.
How many ft-lbs of energy does a .308 180gr Accubond need to expand? How about a .277 130gr Partition? .284 180gr ELD-M? .264 130gr TLR? .243 105gr Berger? .223 77gr TMK? .338 225gr TSX?
What does x amount of velocity tell you wrt terminal ballistics and killing an animal? What does y mass tell you? What does z bullet construction tell you? Alone, nothing tells you anything. Your question is nonsensical.Yes, energy exists. So tell me how to use that number? What does “X” amount of ft-lbs of energy tell me about terminal ballistics and killing animals?
Without cross referencing anything what’s the answer to this-
What does x amount of velocity tell you wrt terminal ballistics and killing an animal? What does y mass tell you? What does z bullet construction tell you? Alone, nothing tells you anything. Your question is nonsensical.
Exactly. And not just bullet material but also the material properties of what the bullet is entering and encounters along the way. There is a reason finite element modeling exists and that's because in order to answer complex physical questions you need more than just a single value that you read on a box.These discussions are always so productive.
'Kill' is a pretty broad definition. A better question might be which one produces a wider and longer wound channel.
Energy and Velocity can tell us very little if we don't know the construction of the bullet. Jacket thickness, lead and jacket hardness, and shape of the bullet all come into play.
"There is no available math equation that can tell you how deep a bullet will penetrate, nor how wide the wound will be, nor the shape of it. If you want to know that, you have to shoot that bullet into tissue or properly calibrated tissue simulate at varying impact velocities"No, it’s not.
Those manufactures design and engineer projectiles to work within a certain velocity window. Most bullets will get decent upset/expansion at 2,000fps impact. Expansion of more than caliber diameter for the above bullets are +/-, in order, 1,800fps/1,750/1,700/ 2,000/1,850/1,700/2,200 fps impact speeds. And, for most of them, that is consistent across the whole bullet line regardless of caliber. The Ft-lbs of energy is all over the map for those impact speeds, yet wounds for like bullets are very similar.
There is no available math equation that can tell you how deep a bullet will penetrate, nor how wide the wound will be, nor the shape of it. If you want to know that, you have to shoot that bullet into tissue or properly calibrated tissue simulate at varying impact velocities. Varying impact velocities: not varying impact ft-lbs of energy.
A .308 200gr Partition at 2,800fps impact, and a .243 95gr Partition at 2,800fps impact have vastly different ft-lbs of energy, yet both are designed to work correctly at the same speed, and wounds will be similar- with the 95gr looking like a smaller version of the 200gr.
There is not one bullet from any major manufacturer that is designed around a certain ft-lbs of energy. They are 100% designed around a velocity window and then almost all are engineered to penetrate and expand a certain way in that velocity window in calibrated 10% ballistics gel.
No, you can certainly model it using multiphysics software and I would seriously bet that the companies who design bullets do this before they spend time manufacturing anything. So there literally are math equations that handle it, or you couldn't model it.
"There is not one bullet from any major manufacturer that is designed around a certain ft-lbs of energy. "
Again, they probably model everything.
Exactly. And not just bullet material but also the material properties of what the bullet is entering and encounters along the way. There is a reason finite element modeling exists and that's because in order to answer complex physical questions you need more than just a single value that you read on a box.
Edit: And I should say, when a company says their bullet expands at a certain velocity it's because "velocity" is the easiest/simplest thing for the end user to quantify. It is NOT because that's the only thing that matters.
FEA is beyond the capabilities of the average joe (wish I had the software and data for these types of discussions), so all we have to go off of is the manufacturers' velocity window. It's not that energy isn't important, but unless manufacturers start offering energy spreadsheets for each product line and caliber it is kinda useless in making a decision on what will and won't work."There is no available math equation that can tell you how deep a bullet will penetrate, nor how wide the wound will be, nor the shape of it. If you want to know that, you have to shoot that bullet into tissue or properly calibrated tissue simulate at varying impact velocities"
No, you can certainly model it using multiphysics software and I would seriously bet that the companies who design bullets do this before they spend time manufacturing anything. So there literally are math equations that handle it, or you couldn't model it.
"There is not one bullet from any major manufacturer that is designed around a certain ft-lbs of energy. "
Again, they probably model everything. If they don't, what on earth are they doing? At work we model everything from the fluid dynamics in our systems to the structural mechanics of the systems themselves. Similarly we model how blasts affect tissues. It would be malpractice to blindly test or design things.
The speed you keep talking is just a part of what goes into making those bullets act the way they do. That's just how it physically works. I don't know what else to say.
Software like COMSOL is readily available if you have the money, yes. We model other types of tissue interactions for stuff like blast propagation and tissue damage and find that it is pretty accurate. Not perfect, of course, but close enough to understand what’s happening. It’s difficult to recapitulate most things experimentally as well, though. An example of that is how a phantom (like ballistics gel) isn’t a perfect analog for tissue either but it is a good enough approximation for certain types. I have thought about doing ballistic modeling, though, because it could be fun (just time and resource intensive)!So is the “multiphysics software” readily available, and what has been your experience in the correlation of what it outputs versus what was seen in animals?
I’m not guessing what they do.
Yes everything is modeled, no you aren’t using a bullet that was modeled as to what it will do in tissue and then packaged in a box to be sold. That bullet was tested in tissue, or now for the most part in tissue simulate. Very often, the “model” was not correct and the projectile had to be tweaked.
Using them as an example because there is a large body of work publicly available, the FBI Terminal Ballistics Section is the largest, best researched, peer reviewed, and best funded ballistics lab in the world. They are also the only closed loop ballistics entity that exists. Every research project and study has consistently resulted in the finding that ft-lbs of energy is not a wounding mechanism and can not and will not tell you what kind of damage to expect in tissue.
There are two broad categories- math based metrics, and damage based metrics. Math based metrics give absolutely no functional information to the user- it’s numbers that do not tell someone what to expect in tissue. Damage based metrics on the other hand, literally show you what to expect in tissue- how deep, how wide, and the shape of damaged tissue.
Again, I’m not saying velocity isn’t important because it obviously is. For whatever their test material is, the velocities listed are the minimum (or range) at which their projectiles start to deform upon impact. That range will naturally change depending on the material, though, and entering a mouse will differ from an elephant. And, importantly, that velocity range is the easiest thing for the end user to look at when they want to know if a projectile will function as advertised.
tl;dr Saying something doesn’t matter is just a pet peeve of mine because stuff is complex
Uh oh, now someone is going to come in and say there's no such thing as hydrostatic shock.Like the article states the hydrostatic shock incapacitated them then death soon followed.
Not allowing what....heavier bullets?Cept in states still not allowing it.
No, I was being dumb and referring to Sunday hunting.Not allowing what....heavier bullets?
I realize my comment is oversimplified and dumbs it down...but its been a clear difference: a little heavier is better when it comes to the longer shots.
FWIW, all of the kills Ive seen with a rifle are within 400yds.....well within the accepted energy range for each big game cartridge.
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