Find the flaw in my logic .300wm vs .338wm (Benelli R1)

[d2wing]

The physics of energy has been established for about 300 years. It wasn't made up by Roy Weatherby. It is not an old wives tale. Energy is what propels the bullet. It is what is used up in the wounding of the target. It is not separate. There is no other force involved. The real discussion is how that energy is employed by a projectile. Momentum is the tendency of an object to remain in motion. It is not a measurement of work. The bigger and faster a bullet is, the more energy it takes to propel it. The more is potentially used by the target. How it is used up depends on many factors. That is the subject of discussion. Every cartridge and its bullet is a compromise depending on its intended use. In my opinion, both rounds would work. Do both meet the requirements of the guide? Otherwise just preference for close range.

 

[Varminterror]

Here are a few realities which have been completely ignored in the debate of physics above:

1) Velocity is a fundamental parameter of Kinematics. Mass, Time, & Velocity are the foundation of all other parameters. Relativisms among these three parameters are the purpose for most other calculated values among the entire study of physics.

2) Kinetic Energy is NOT conserved in real world, inelastic collisions - MOMENTUM, however, IS conserved. Which is WHY we (using "we" to refer to myself and other engineers and physicists which actually do these calculations) use MOMENTUM to calculate the WORK done within the system - Work being defined as the difference in Energy before vs. after. So we start with a given mass & velocity, which is used to calculate both the kinetic energy and momentum of the projectile. A common misconception is that if a bullet stops within the animal, its entire Kinetic Energy is "dumped" into the animal, because it isn't - we know we have Kinetic Energy lost as heat, sound, and destruction to the bullet itself. (Just for fun, the Rate of Work, is Power - Work/time - meaning how fast is the Work being done... But this is differential calculus in the case of a decelerating bullet, so it gets pretty messy pretty quickly). So we really can't use KE to do anything - we have to use Momentum to calculate BACK to kinetic energy at the end, and we immediately see a LOT of KE is wasted in other things which are NOT creating tissue damage.

3) No, the TKO is NOT a relevant value for any other application in any other branch of physics or engineering - but it IS simply the product of momentum and bullet diameter. In this case, it has been used with relatively high success as a proxy for understanding momentum transfer - simply, a bigger diameter bullet hits more animal than a smaller bullet, so the same momentum on a bigger diameter bullet will transfer momentum more rapidly (which means transferring KE more rapidly, aka, doing more WORK in less time, impacting with more Power). Sectional Density is another proxy for this same consideration - it's not so different than considering the Ballistic Coefficient of a bullet in flight as a proxy for its Coefficient of Drag (not so different than things like "slump factor" for mixing concrete either - an indirect measurement used as a proxy for a relatively complex and relatively unmeasurable quantity that is Work(done to animal) and KE(out). So we can look at something simple like bullet diameter or sectional density as proxies for for the more complex value. It's not "good," but it's better than nothing, and it's certainly closer than KE since all of the terms in momentum, and subsequently TKO are linear rather than Power Functions.

So it does remain fair to point out that Kinetic Energy is an exceptionally poor proxy for the killing potential of a bullet - but it's also impossible to have high momentum without also having significant kinetic energy. We can't REALLY only use TKO either, but it's a hell of a lot more relevant to how the rest of physics is done than is a simple statement of KE.

SO.... What really remains, is the fact there's no definitive science either way which suggests 338wm is a better or worse choice than 300wm for the OP's application...

 

[d2wing]

now lets look at what you said



Not a single one of those quotes say that energy is irrelevant. What they do say when read in their context is that bullet energy by itself is not a useful metric for comparing two projectiles. If you took any of them to mean that kinetic energy is not required to cause wounding then you are either not very good at reading or you are just arguing in bad faith.

Really. You can't read what Craig wrote? A number of times he claimed that Energy is useless, meaningless, was invented recently, an old wives tales etc. He has said the same things for years.

 

[luv2safari]

The buffalo pictured below took one 300 Gr .375 H&H round through the top of the heart. He went about 20 yards and keeled over grave yard dead.
View attachment 1188859

This buffalo bull took two .470 NE 500 Gr bullets the first in a 500 Gr Barnes X punched trough both lungs the second a solid punched through a single lung and stopped up in the neck muscle both were a bit low.

View attachment 1188860

We gave the bull about 20 minutes and could hear his labored breathing about 100 yards back in the thick Jesse brush. The PH and I approached him in extremely tight cover and the instant the bull saw us at about 15 yards he launched into a full charge. The PH and I we’re both carrying .470 double guns and the instant the bull jumped up we both hammered him with a 500 Gr solid Squarely in the chest just above the breast bone. The bull showed no reaction to taking a pair of .470’s delivering over 10,000 Ftlbs of energy, my next shot was aimed at the forehead and my bullet deflected on a small tree if you look at the right ear you’ll see a perfect outline of a sideways .470 bullet that pierced the ear then harmlessly grazed the neck.

The PH fired his second barrel hitting the bull just under the spine and turning him, giving me enough time to do an emergency reload and sending my next bullet into the side of his neck breaking the spine and killing the bull. You can see that hole just below the graze mark.

I‘ll ask the question here. Did energy matter in that charge?

Apples and oranges.

Buffalo are hard to shock. Brown bears are difficult to shock. But, they do shock, and that's a big factor when hunting them. The mass of energy delivered, especially when one of them is about on top of you, can make the difference in whether or not they kill you before they die or at least drop for a moment.

 

[crstrode]

I already have an R1, looking at getting a new barrel, ideally this will be capable of going to Alaska with me some day, and many outfitters advertise that they require a minimum .300 win mag (need to actually talk to a few to see how they feel about 7mmstw). This brings it down to .300 vs .338, I don't actually care for either cartridge. That being said, I have never found an instance, hunting, that couldn't be solved by the .300 that the .338 would have solved betterer, especially with bonded/partition/monometal bullets.... soooo is there any REAL reason to go .338? This will only be shot enough to stay proficient, not a regular use rifle.

The flaw in your logic?
You are over-thinking.

 

[d2wing]

Here are a few realities which have been completely ignored in the debate of physics above:

1) Velocity is a fundamental parameter of Kinematics. Mass, Time, & Velocity are the foundation of all other parameters. Relativisms among these three parameters are the purpose for most other calculated values among the entire study of physics.

2) Kinetic Energy is NOT conserved in real world, inelastic collisions - MOMENTUM, however, IS conserved. Which is WHY we (using "we" to refer to myself and other engineers and physicists which actually do these calculations) use MOMENTUM to calculate the WORK done within the system - Work being defined as the difference in Energy before vs. after. So we start with a given mass & velocity, which is used to calculate both the kinetic energy and momentum of the projectile. A common misconception is that if a bullet stops within the animal, its entire Kinetic Energy is "dumped" into the animal, because it isn't - we know we have Kinetic Energy lost as heat, sound, and destruction to the bullet itself. (Just for fun, the Rate of Work, is Power - Work/time - meaning how fast is the Work being done... But this is differential calculus in the case of a decelerating bullet, so it gets pretty messy pretty quickly).

3) No, the TKO is NOT a relevant value for any other application in any other branch of physics or engineering - but it IS simply the product of momentum and bullet diameter. In this case, it has been used with relatively high success as a proxy for understanding momentum transfer - simply, a bigger diameter bullet hits more animal than a smaller bullet, so the same momentum on a bigger diameter bullet will transfer momentum more rapidly (which means transferring KE more rapidly, aka, doing more WORK in less time, impacting with more Power). Sectional Density is another proxy for this same consideration - it's not so different than considering the Ballistic Coefficient of a bullet in flight as a proxy for its Coefficient of Drag (not so different than things like "slump factor" for mixing concrete either - an indirect measurement used as a proxy for a relatively complex and relatively unmeasurable quantity that is Work(done to animal) and KE(out). So we can look at something simple like bullet diameter or sectional density as proxies for for the more complex value. It's not "good," but it's better than nothing, and it's certainly closer than KE since all of the terms in momentum, and subsequently TKO are linear rather than Power Functions.

So it does remain fair to point out that Kinetic Energy is an exceptionally poor proxy for the killing potential of a bullet - but it's also impossible to have high momentum without also having significant kinetic energy. We can't REALLY only use TKO either, but it's a hell of a lot more relevant to how the rest of physics is done than is a simple statement of KE.

SO.... What really remains, is the fact there's no definitive science either way which suggests 338wm is a better or worse choice than 300wm for the OP's application...

I agree that momentum is converted to Kinetic energy, but momentum, acceleration, is not imparted to the body of the target, It is energy that does the work. Momentum remains if the bullet leaves the body. Yes, you can infer that the amount of momentum equates to the amount of energy. That doesn't change that it is energy that does the work and how it is calculated, and it doesn't address how that energy is used or what bullet to use. If TKO helps with understanding how energy is applied and bullet selection, I suppose it is useful but unnecessary and not valid. We should all know that bigger and faster is better. Simplification is one thing, outright wrong is another and I don't see how misleading ever helps.
Kinetic energy is the amount of energy that can be potentially used, it doesn't know if the bullet is big or small, what shape or construction or where it is put. It doesn't dictate what cartridge to use. Neither does momentum. And the calculations don't change because people don't understand the. It's the same as changing history because people don't like it.

 

[Varminterror]

Energy is what propels the bullet

Force is what propels the bullet.

 

[Varminterror]

momentum, acceleration, is not imparted to the body of the target,

This is ABSOLUTELY incorrect.

You are violating one of the Laws of Motion which you're claiming to uphold in this post.

 

[d2wing]

This is ABSOLUTELY incorrect.

You are violating one of the Laws of Motion which you're claiming to uphold in this post.

Only if the body is moved by the bullet. Do you mean because a part of the body is moved or because the momentum of the bullet changes. Not sure what you mean. Momentum is the tendency of a body to stay in motion, correct?
Energy is created by expanding gasses is it not?
It's been 50 years so yeah, I may be incorrect on terminology. I don't object to correction. I do want to move on.

 

[Varminterror]

Yes, you can infer that the amount of momentum equates to the amount of energy.

No, you cannot. Because momentum does not equate energy. This is another example of your fundamental misunderstanding of the science you're claiming to support your argument.

That doesn't change that it is energy that does the work and how it is calculated, and it doesn't address how that energy is used or what bullet to use.

Again, these statements make it absolutely obvious that you do NOT understand that Kinetic Energy is NOT conserved, because, in fact, REAL physicists and engineers DO absolutely and irrefutably use CONSERVATION OF MOMENTUM to calculate the remaining Kinetic energy after collision which becomes the basis for what Work is done. Bluntly, you're wrong, and don't understand the science you're trying to describe. Anyone who made it through high school physics knows how to apply conservation of momentum to translate BACK to Energy at final state, and subsequently calculate Work.

If TKO helps with understanding how energy is applied and bullet selection, I suppose it is useful but unnecessary and not valid. We should all know that bigger and faster is better. Simplification is one thing, outright wrong is another and I don't see how misleading ever helps.

TKO isn't invalid, and certainly isn't "outright wrong." TKO is Momentum - which is the ONLY correct value which can be used for these calculations - times bullet diameter: and when comparing two relatively similar bullet diameters, this effectively comes out in the wash... So it's not invalid, it's not outright wrong, and it's not misleading. It's not as accurate as it could be, which is true of all approximations and functional proxies, but what it IS is fundamentally MORE correct than Kinetic Energy.

Kinetic energy is the amount of energy that can be potentially used, it doesn't know if the bullet is big or small, what shape or construction or where it is put. It doesn't dictate what cartridge to use. Neither does momentum. And the calculations don't change because people don't understand the. It's the same as changing history because people don't like it.

All of this is is just dismissive nonsense. Nobody is "changing history" by correcting you that Newton's 1st law = the conservation of momentum is absolutely applicable. And naturally, Potential Energy is the amount of Energy which can be Potentially used, hence Potential Energy, which is the spectral opposite of Kinetic Energy. What you may have meant to say is that Kinetic Energy is a measure of the maximum Work available to be done by an object in motion, but it remains untrue to say that Kinetic Energy is conserved in any way as an expectation for the work to be done - because Kinetic Energy is NOT conserved in real world collisions. You keep throwing around the "Laws of Energy" which in no way apply in this discussion - you are convoluting Newton's Laws of Motion with the Laws of Thermodynamics, as the "laws of energy" are 1) Energy is never created or destroyed, 2) For all natural processes, Entropy increases, and 3) Absolute Zero (0*k) is defined as the Zero Entropy State. You're talking about laws of motion, and neglecting the first of them.

 

[Varminterror]

Only if the body is moved by the bullet. Do you mean because a part of the body is moved or because the momentum of the bullet changes. Not sure what you mean. Momentum is the tendency of a body to stay in motion, correct?
Energy is created by expanding gasses is it not?

1st law of thermodynamics, Energy is never created or destroyed. So NO, energy is NOT created by expanding gases.

You are out of your depth.

 

[d2wing]

1st law of thermodynamics, Energy is never created or destroyed. So NO, energy is NOT created by expanding gases.

You are out of your depth.

Ok, you are correct. 50 years s along time. I forgot most of that.

 

[CraigC]

Good Lord. If this devolves into basic physics, it'll go nowhere.

People seem to have a difficult time separating the existence of energy in the abstract, as something Isaac Newton quantified and the use of energy as a measure of terminal effect by the hunting industry. Context is everything. I never said energy did not exist or wasn't at work in anything that moves. Simply that to use energy as a measure of terminal effect, how effective a projectile is at destroying a soft target, is a misapplication. It just has too many holes in it. As long as people depend on that arbitrary number, there can be no realistic discussion about this subject. This is a perfect example.

So far no one has rationalized the examples I gave.

Insufficient energy is a real problem, otherwise we wouldn't see minimum energy requirements from guides and regulations.

They have to have some standard and since 99.99% of hunters are using rifles, it mostly works.

Going back to the example that CraigC keeps referring to (150 gr .308 @ 3,100 fps and 3,200 ft-lbs; 220 gr .308 @ 2400 fps and 2,800 ft-lbs; 300 gr .44 @ 1,450 fps and 1,400 ft-lbs), why isn’t the 150 gr. .308 obviously the best choice for large, heavy game like the buffalo he loves to show off? It would be, if you could design a 150 gr bullet that would reliably punch through heavy bone, continue to penetrate all the way to the vitals and then and only then rapidly deform as it passed through the vitals of the buffalo. Since this is very difficult to do, the 150 gr bullet is not the best choice.

If you designed a 150gr bullet that did all that, it wouldn't be 150gr any more. It would probably be 200-220gr. Mass makes a huge difference in penetration, as does construction. Energy trivializes the former and ignores the latter.

I would ask CraigC and others who have hunted buffalo why is .375 H&H firing a smaller diameter bullet of the same weight (300gr) as CraigC’s .44 or even lower weight (260gr) considered an excellent large, heavy game cartridge. Could it possibly be the extra 1,000 – 1,300 fps in velocity?

What does that .375 expand to? How does that limit penetration? The .44 is a solid and does not deform at all.

If both effectively get the job done, what does the discrepancy in energy tell us?

 

[Varminterror]

So far no one has rationalized the examples I gave.

Which examples - it's 5 pages...

 

[CraigC]

Any Army research involving FMJ is entirely irrelevant. Context matters.

 

[H&Hhunter]

Apples and oranges.

Buffalo are hard to shock. Brown bears are difficult to shock. But, they do shock, and that's a big factor when hunting them. The mass of energy delivered, especially when one of them is about on top of you, can make the difference in whether or not they kill you before they die or at least drop for a moment.

I can’t argue with that. I’ll say this a bigger thump MIGHT make all the difference in a life or death situation with a buff. I personally like a bigger thump delivery system.

 

[Varminterror]

People seem to have a difficult time separating the existence of energy in the abstract, as something Isaac Newton quantified and the use of energy as a measure of terminal effect by the hunting industry.

Only people who really don't understand what they're observing, and worse, people who don't understand what they're saying.

Any Army research involving FMJ is entirely irrelevant. Context matters.

Not at all irrelevant - we know with FMJ's, momentum is not transferred as quickly as with expanding bullets, so rather elementary physics DOES expand that FMJ's don't transfer momentum as efficiently or as quickly, such less Kinetic Energy is used to damage tissue, less Work is done to the animal (kinetic energy out vs. in), and the impact involves less Power (Work done over time).

 

[CraigC]

Which examples - it's 5 pages...

Mainly the .30-06 examples, to keep things simple.

Case in point, the vaunted .30-06.

150gr at 3100fps = 3200ft-lbs.
220gr at 2400fps = 2800ft-lbs.

That's 400lbs in favor of the lighter bullet. If the 150 is only good for deer but the 220gr is good for any and all on the North American continent and much of Africa, of what use is the energy calculation? It ain't worth jack spit.

Meanwhile, a 300gr .44 at 1450fps produces 1400ft-lbs. Exactly half that of the 220gr .30-06 but is more suitable to critters like this than any .30 caliber rifle. Does it not at least tell us to question the validity of energy as a means to measure terminal effect?

 

[CraigC]

Not at all irrelevant - we know with FMJ's, momentum is not transferred as quickly as with expanding bullets, so rather elementary physics DOES expand that FMJ's don't transfer momentum as efficiently or as quickly, such less Kinetic Energy is used to damage tissue, less Work is done to the animal (kinetic energy out vs. in), and the impact involves less Power (Work done over time).

Maybe within the context of military usage and shooting the enemy. They do not rely on flat nosed or expanding bullets for tissue destruction. Velocity is the only avenue. They are also not seeking a quick end to the target's life. Just to get it out from behind the trigger.

 

[d2wing]

Good Lord. If this devolves into basic physics, it'll go nowhere.

People seem to have a difficult time separating the existence of energy in the abstract, as something Isaac Newton quantified and the use of energy as a measure of terminal effect by the hunting industry. Context is everything. I never said energy did not exist or wasn't at work in anything that moves. Simply that to use energy as a measure of terminal effect, how effective a projectile is at destroying a soft target, is a misapplication. It just has too many holes in it. As long as people depend on that arbitrary number, there can be no realistic discussion about this subject. This is a perfect example.

So far no one has rationalized the examples I gave.



They have to have some standard and since 99.99% of hunters are using rifles, it mostly works.



If you designed a 150gr bullet that did all that, it wouldn't be 150gr any more. It would probably be 200-220gr. Mass makes a huge difference in penetration, as does construction. Energy trivializes the former and ignores the latter.



What does that .375 expand to? How does that limit penetration? The .44 is a solid and does not deform at all.

If both effectively get the job done, what does the discrepancy in energy tell us?

I am informed that I am over my head and I have to agree. I still don't agree with some of what you said, but I want to bury the hatchet. I am out of here.

 

[CraigC]

Do you think you would have gotten the same result with a 520 gr bullet from a .500 S&W magnum?

Pretty much. Does that alter your perspective?

 

[CraigC]

I am informed that I am over my head and I have to agree. I still don't agree with some of what you said, but I want to bury the hatchet. I am out of here.

The bottom line here is that there is no reason for any of it to get personal. We're talking about shooting critters, which in the grand scheme of things, ain't that big a deal.

 

[Varminterror]

I don't recall exactly the example @CraigC mentioned, but it seems like it might have been between 243win and 44mag. A 100grn bullet at 3000fps has 1998 ft.lbs. of KE, while the 44mag's 300grn slug at a paltry 1300fps has only 1125 ft.lbs., so why can Craig reliably knock down buffalo with the 44mag, but the 243win certainly wouldn't be recommended? Eliminating the proxy that is the TKO inclusion of bullet diameter, we can simply look at raw momentum - the 44mag has 55.7 lbmft/sec of momentum, while the 243win bullet only has 42.9 lbmft/s... We can certainly comprehend as well that the relatively similar sectional density of a 100grn 6mm and a 300grn 44cal slug suggest relatively similar penetration potential, BUT we can observe the larger cross-sectional area - 0.15sq.in. as opposed to 0.05sq.in. - will give the 44mag better opportunity to put more momentum, more quickly, into the animal... So yeah, it really is pretty simple to describe all of these examples with REAL physics, not the half-understood pseudoscience folks try to kick around online...

 

[Varminterror]

Maybe within the context of military usage and shooting the enemy. They do not rely on flat nosed or expanding bullets for tissue destruction. Velocity is the only avenue. They are also not seeking a quick end to the target's life. Just to get it out from behind the trigger.

And we can well describe via modulus of elasticity, plastic deformation, elastic deformations, etc why impact velocity matters in a game where we are restricted to non-expanding FMJ's... But we really CAN relate the difference between slow bullets with large frontal areas vs. small diameter, high velocity spitzers, in terms of potential to do the job.

Not everyone knows how to do that math, even though it really is relatively simple (like you mention, killing animals just isn't that complicated, nor is elementary ballistics - when we start talking about differential rates of momentum flux, stuff gets more interesting), and I do appreciate that you've had many years of arguing against kinetic energy as a measure of performance, myself the same, so you've been pressed as far as can be away from accepting any mathematic or scientific explication, but I know you're also smart enough to realize, our ONLY source of knowledge in physics as a body of science has come from OBSERVATION of real world reactions. There's theoretical physics out there which is grossly unsubstantiated, but even that remains to exist only as an attempt to understand the observations we see in the REAL WORLD. Ballistics aren't so complex, we've had them pretty well figured out for a long time.

 

[wombat13]

now lets look at what you said



Not a single one of those quotes say that energy is irrelevant. What they do say when read in their context is that bullet energy by itself is not a useful metric for comparing two projectiles. If you took any of them to mean that kinetic energy is not required to cause wounding then you are either not very good at reading or you are just arguing in bad faith.

This is a literal quote in that I included in the post you are responding to:

"I'll say it again, energy is only useful as a marketing tool for selling velocity." CraigC wildly overstated his case and tried to walk it back later but still keeps making obnoxious statements toward other posters.