Loosedhorse
member
Then they are wrong. The momentum is 0.76 lb-sec, or 24.4 lb-ft/sec. Note that lb refers to force in lb-sec, and to mass in lb-ft/sec.
How much energy in ft lbs ?
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marcclarke
Member
Shall we talk about slugs as the proper unit of mass in the Imperial system?
Just leave it in metric FFS. :banghead:
Kachok
Member
Yeah that is alot less confusing I think, why on Earth we in the USA stick to the imperial system is beyond me, metric makes SOOOO much more sense when we are talking science.
Back to my original point the 223 in my example makes aprox half the momentum as the 240gr 44 cal bullet despite it's higher energy, this helps us account for the more consistent wound path of the larger caliber, and helps us understand why larger calibers and or higher SD bullets are more efficient killers when we speak in terms of energy (though not as much in terms of recoil) so putting a blanket statement out like "Nothing less then 1,000 ft/lbs of energy is sufficient for deer" is simply silly, the performance of that 44 cal in the ballistic gel test I posted is comparable to small caliber hunting rounds of much higher energy in terms of the total amount of tissue damage, the volume of the PWC (permanent wound cavity) is impressive, not only did it pass through a standard 16" BG block but penetrated 8" into the poly backstop. The 223 in contrast made a pencil thin wound tract for the last several inches and only penetrated a total of 15 inches, and remember that is an advanced bonded bullet not some oldschool silvertip that would loose 1/2 it's mass on contact.
The best formula to predict total wounding potential that I have come across is the one written by Chuck Hawks, it takes into account the aspects of mass, caliber, energy, and SD, and while I don't totally agree with the values placed on each it is a solid place to start IMHO.
Back to my original point the 223 in my example makes aprox half the momentum as the 240gr 44 cal bullet despite it's higher energy, this helps us account for the more consistent wound path of the larger caliber, and helps us understand why larger calibers and or higher SD bullets are more efficient killers when we speak in terms of energy (though not as much in terms of recoil) so putting a blanket statement out like "Nothing less then 1,000 ft/lbs of energy is sufficient for deer" is simply silly, the performance of that 44 cal in the ballistic gel test I posted is comparable to small caliber hunting rounds of much higher energy in terms of the total amount of tissue damage, the volume of the PWC (permanent wound cavity) is impressive, not only did it pass through a standard 16" BG block but penetrated 8" into the poly backstop. The 223 in contrast made a pencil thin wound tract for the last several inches and only penetrated a total of 15 inches, and remember that is an advanced bonded bullet not some oldschool silvertip that would loose 1/2 it's mass on contact.
The best formula to predict total wounding potential that I have come across is the one written by Chuck Hawks, it takes into account the aspects of mass, caliber, energy, and SD, and while I don't totally agree with the values placed on each it is a solid place to start IMHO.
Loosedhorse
member
IMHO any formula that doesn't take into account bullet type (spitzer, RN, FP, HP, or fragmenting) is lacking.
The best formula to predict anything would be the one that has had its predictions verified, either in an experimental setting or in collected field data. Without that, it's just another formula, right next to Taylor KO and Hatcher's Relative Stopping Power Index. Any of those formulae is a good place to start, but without data to test and refine them, they can't get beyond the starting line.
Kachok
Member
That would be why I said wounding POTENTIAL, because bullet construction is a vital component but that is no mathematical method to quantify the aspect of bullet construction, the only thing we can do is know how our bullets perform at various speeds, I know very well how each and every one of the bullets I load perform on target. The most important aspect is knowing your penetration, fragmentation and level of expansion are a distant second to this.
The TKO formula is simply silly, any formula that says a beachball at 10 fps is four times as deadly as a .50 BMG has obvious flaws
Even Just talking in the context of just bullets the flaws in TKO are easily noticeable, according to the TKO a 45 ACP is more lethal then a 243 or 6.5x55 anyone with any hunting experience what so ever should instantly know that not to be the case, they are not even close.
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Loosedhorse
member
I appreciate your clarification of your use of the word potential. And how does one verify that any given formula predicts wounding "potential" accurately?
How does one even define this "wounding potential"? Or should I ask how Chuck Hawks defines it? I've been to his website, but haven't found his "wounding potential" formula. I did find what he's calling his "Rifle Cartridge Killing Power Formula". He specifies no bullet type (beyond a "bullet is appropriate for the game and conditions")...
And does not shout "POTENTIAL" at his readers.
Kachok
Member
I am no die hard Chuck Hawks fan, in fact I don't think I'll ever forgive him for bashing the Tikkas like he did, but I think he did a pretty fair assessment of how important his formula was, and I quote.
"The most important factor in killing power, by far, is bullet placement. The second most important factor is probably bullet terminal performance. The third most important factor is probably the physical and mental state of the game animal in question at the moment it is shot. This formula takes into account none of those factors. Unfortunately, those key factors are not quantifiable, at least by me. So, I am assuming that the hunter knows how to shoot, where to put the bullet, and that the bullet is appropriate for the game and conditions."
He did address the bullet construction just was not able to place a value on it, and I don't think anyone can.
"The most important factor in killing power, by far, is bullet placement. The second most important factor is probably bullet terminal performance. The third most important factor is probably the physical and mental state of the game animal in question at the moment it is shot. This formula takes into account none of those factors. Unfortunately, those key factors are not quantifiable, at least by me. So, I am assuming that the hunter knows how to shoot, where to put the bullet, and that the bullet is appropriate for the game and conditions."
He did address the bullet construction just was not able to place a value on it, and I don't think anyone can.
Kachok
Member
NOPE, nothing considered remotely accurate anyway, too many variables involved, the same bullet that performers perfectly at 2800fps could have a complete failure at 3000fps
The chart references standard values for velocity. It might mention several different loadings though... But I know it exists.
Where like a 22 might score a 6 and a 357 might get a 44 or something like that...
Loosedhorse
member
Sounds similar to Taylor KOs: 1.3 for .22, 20 for .44 Mag.
It's not ALL a direct relationship.
Mass and momentum are directly linearly related.
Mass and energy are directly linearly related.
Velocity and momentum are directly linearly related.
Velocity and energy are not directly linearly related.
It's not possible to constructively discuss rifle ballistics, momentum and energy formulas, etc. without talking about mathematics.
Do you remember starting this over my use of a single word in a sentence that actually provided full clarification, using standard mathematical concepts and terminology, of what I meant when I used it?
So at what point did it go from being a good thing to point things out that might be misleading or in error, to being something worthy of ridicule and scorn? The only criteria I can see is being applied is which way the finger is pointing...
Here's another case in point. So it's ok to nitpick over the meanings of common words when you do it but when anyone else does it, they deserve a dressing down.
Apparently it's even ok to criticize/comment negatively on something as minor as someone using capital letters to emphasize a particular word as long as it's the right person doing the criticizing.
All I'm saying, is that maybe just a tiny bit less of a double standard would be refreshing.
Yeah, who cares about being precise and accurate when it comes to rifles, of all things!
I agree.
Unfortunately based on the number of variables involved and the complexity of modeling/characterizing/predicting the response of a living animal to a bullet strike, I feel very safe in saying that there won't be any simple formula (something that can be calculated from a few numbers and that provides a single number output) that will provide any more accurate results than what we have now. And just to be perfectly clear, I'm not saying that anything we have now provides results that are accurate.
The FBI does testing with handgun rounds to try to quantify wound volume to be used as a measure of terminal effect. While there is certainly some value to knowing those figures, they don't begin to tell the whole story.
That sort of information would be even less valuable when applied to rifles given the fact that the stretch cavity is a fairly reliable wounding mechanism in many rifle calibers and it's totally neglected by the wound-channel measurement method used in collecting that data.
Short answer is that there's no chart like you describe that I'm aware of and even if there were, I certainly wouldn't rely on it too heavily.
Loosedhorse
member
Your opinion. Actually, I think the discussion only became obscured when you started claiming that I was inventing new mathematical (and English language) concepts. Such comments by you have impeded, not helped, "constructive" discussion.
What I remember is how quickly you changed from the reasonable "it's all in how you look at it" to increasingly viscious and sustained attacks on me (flat out implying that I didn't understand math, physics or English); and as your attacks became more and more unreasonable, so your defending your attacks became more and more desperate and lengthy (note example above).
While you've been discussing "direct" and "primary" and claiming that I've come up with "terminology out of the blue" and "invented/made up" concepts--and while you've been making up "helpful" words like glerb and blivet--I was following the discussion and helping to solve the lb (force) vs lb (mass) issue. So, who exactly has been contributing to a "constructive" discussion here, and who has been distracting from it and obscuring it?
If you want to continue to make this about attacks, fine: I can play. Personally, I'd prefer you go back to your earlier position: "it's all in how you look at it". And how I look at it is (what? Fourth time I'm stating this?) that in rifle ballistics, mass is more important to momentum than energy--even though you are free to disagree.
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Old Time Hunter
Member
Read this someplace:
Winchester's 44WCF has dispatched more men, good and bad, and put more food on the table than any cartridge ever made
Suppose that would include deer.
My grandfather had no problem with whitetail, if he figured he could hit it, he would...no matter what the distance. And because his '92 had a broken cartridge lifter, he used it as a single shot. Cast his own bullets and used black powder (he made himself)...but that .44-40 never left him without meat on the table.
Winchester's 44WCF has dispatched more men, good and bad, and put more food on the table than any cartridge ever made
Suppose that would include deer.
My grandfather had no problem with whitetail, if he figured he could hit it, he would...no matter what the distance. And because his '92 had a broken cartridge lifter, he used it as a single shot. Cast his own bullets and used black powder (he made himself)...but that .44-40 never left him without meat on the table.
.30-30 holds the title of most prolific deer getter.
Float Pilot
Member
My personal minimum for modern cartridges of 375 and smaller....for medium (deer, goats & caribou) and larger game is 1,000 foot pounds of energy and around 1,800 fps remaining velocity for bullet expansion.
For example my 24 inch BHW barreled AR in 6.8mm SPC will now shoot a 110 grain Nosler Accubond bullet at 3,020 fps. That load holds 1,000 foot pounds out to 400 yards.
Since my personal max hunting distance is 300 meters, (except for mountain goats) that load works just fine.
For example my 24 inch BHW barreled AR in 6.8mm SPC will now shoot a 110 grain Nosler Accubond bullet at 3,020 fps. That load holds 1,000 foot pounds out to 400 yards.
Since my personal max hunting distance is 300 meters, (except for mountain goats) that load works just fine.
Loosedhorse
member
The .44-40 nicely illustrates the energy vs momentum issue. A 64 gr .223 deer load will have over 1000 ft-lb energy at the muzzle and 100 yards, and 27 lb-ft/sec of momentum. The .44-40 200gr at 1245fps has well over that momentum (~35 lb-ft/sec), but comes up quite short of 1000 ft-lb.
So, under the energy requirements some states have, a .223 is a legal big game cartridge, but the .44-40 isn't. We can discuss whether that make sense, but there it is.
So, under the energy requirements some states have, a .223 is a legal big game cartridge, but the .44-40 isn't. We can discuss whether that make sense, but there it is.
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I've not made any attacks on you. I have disagreed with you, and pointed out why some of your terminology is lacking when it comes to describing mathematical relationships. I've also pointed out that while you are certainly concerned about small details of terminology and the definitions of common terms in other posts, you become more than just a little defensive when the same issues regarding your posts are pointed out. None of that constitutes an attack by any stretch of the imagination.
However, if you disagree, then you should report any posts I've made that contain attacks to the staff for appropriate action. That's exactly why the board has staff and they generally appreciate it when they get help from the membership.
I noticed that--I also noticed you discussing math in the process.
I don't believe it does make sense, however I believe I understand why its done. Energy is an easy number to calculate, one that has a basis in science, but most importantly, it's one that's traditionally provided by ammunition makers. In other words, it's simple (even for those who don't want to or know how to do the calculation) to get energy figures for their factory ammunition hunting loads.
I truly believe that if, somewhere along the line, ammunition makers had established the convention of providing momentum figures instead of energy numbers that hunting minimums would be stated in momentum instead of energy. Not because lawmakers believe one is more valid or less valid than the other but simply because one is more convenient than the other.
Tradition, however it is started, is difficult to overcome.
Old Time Hunter
Member
Oh, so very true, especially when started on perception instead of reality.
As far as a .30-30 harvesting more deer, can not argue with that, so I will apologize up front for not debating it any further.
But, the quote did not say "deer", it said "food", and after looking it up, the proper word is "game".
Personally, I've harvested more deer with a .44 Mag, followed closely by a .30-30. But my .444 is closing fast. Kind of retired my '06, 300WM, and a bunch of others that are tiring to carry all day.
But just for thought, took a half way decent Whitetail with my '94 Trapper chambered for the .44 Mag with one shot at a measured (Afterwards) 250 yards while leaning against a tree. Shot down the firelane with a holdover even with his ears, hit him just behind the shoulder. Took a couple of steps and fell over. That was a 240 grain JSP loaded with 23.5 grains of H110. Took almost a full second for the bullet to hit the target. Well at least it seemed.
Loosedhorse
member
And I have not made up any new math concepts, or invented new meanings of words, or anything else you have accused me of doing.
Where's your pot-kettle link again?
Sure: when it clarifies a point; you have used it instead to make obscuring, nonsensical accusations. I am no stranger to or foe of math--that's just another of your little inventions about me.
Interesting that you avoid talking about math when (as with the .223 vs .44-40 example) it makes my point about bullet weight being more important to momentum than to energy in rifle ballistics (fifth time stated). Why you, in disagreeing with me, had to make such a fuss--and still won't let it go? Well, who knows?
Back on topic: I mentioned that some African countries also specify energies as minimum requirements. However, the professional hunters I've talked to there have generally been concerned about three items:
1. Bullet type: they want a tough, penetrating bullet, not something that's going to break up on the skin and msucle before hitting vitals.
2. Caliber: everyone has a favorite caliber for a specific type of game, with some margin around that.
3. Bullet weight: most prefer heavy-for-caliber offerings for big or dangerous game (though lighter bullets in .375 are fine for the smaller plains game).
If you read some of Robertson's books, he always talks about, for any caliber, a preferred velocity of 2100-2500fps, and the heaviest weight bullet that your rifle can throw at that speed. That seems to me an emphasis on both energy (because of the specified velocity) and momentum (because of the specified heavy bullets).
And that's not surprising. It would seem to me that energy figures will select poor hunting loads only in the case of using light, fragile bullets in small-for-game calibers. Energy and momentum figures will often select the same good hunting loads...
Except in the case of older cartridges throwing mid-weight bullets (~200 gr) at moderate velocity (1200-1500fps). Once you get up to large bullets (like with the .45-70), you generally have no trouble making the 1000 ft-lb mark.
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I don't know where you're going with this. If you think I've attacked you (and broken the rules) then report it.
There's no way that what I haven't done changes what you have done and it's ridiculous to claim otherwise.
Except that a few posts ago you stated in no uncertain terms that you were not discussing mathematics and further said that my contention that you were actually discussing mathematics because it's not possible to discuss ballistics/momentum/energy without mathematics was simply "my opinion".
Except I never said any such thing about you.
I made a comment which admittedly used a single word in a manner that could be misconstrued. In all fairness, I didn't even finish the sentence in question without adding additional information which, using standard mathematical terminology, completely clarified my meaning.
You objected to the use, and, if you note, I responded in the spirit of the clarification clause in the original sentence, thinking that you were objecting to the statement as a whole, not understanding for several iterations of post/response that you were focused exclusively on the single word.
When I realized what you were focused on, I retracted/restated my original statement without using the particular word you objected to.
However, in the process of getting to that stage, you posted a number of things that were terminologically/semantically/mathematically problematic. I posted the link and the comments pointing that out because (and I admit that it may have been somewhat petty of me--call it a slight flaw in my character if you wish) it was irritating to see you taking me to task for an isolated circumstance in my post of something that turned out to be a frequently encountered problem in your own posts.
Now, I've retracted my original statement. I've not attacked you. That's all you're getting. If you think you deserve more then take it to the staff and see if they agree. Otherwise, climb down a notch. There's no reason for you to believe that you should be able to pick nits from other members' posts and at the same time feel that you can make multiple errors of the same variety and expect that they should be ignored or exempted from being noted.
I didn't avoid anything, I addressed the point appropriately and mentioned both energy and momentum (both mathematical/scientific concepts) in the process.
Is there something in my response to your statement about the .223 and the .44/40 that you disagree with or take exception to?
Sure, that makes perfect sense. Taking either to excess in a rifle cartridge without a reasonable amount of the other is going to reduce terminal performance, in my opinion. Lots of energy with relatively low momentum will tend towards shallow penetration and a higher chance of bullet failure. Lots of momentum with relatively low energy means rainbow trajectories, no stretch cavity tissue damage and more recoil than you really need to get the job done.
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