If you go by the TKO factor it favors the .44 mag over the .270 Winchester which has a similar TKO to the 30-30. The .270 is more deadly than the .44 and the 30-30 with the right bullet. It carries significantly more energy and velocity than either, and has higher SD bullets available.
Handgun stopping power
- Thread starter Polglock
- Start date
If you go by the TKO factor it favors the .44 mag over the .270 Winchester which has a similar TKO to the 30-30. The .270 is more deadly than the .44 and the 30-30 with the right bullet. It carries significantly more energy and velocity than either, and has higher SD bullets available.
the advanced physics crap makes my head hurt...in particular the problem with the swimmer, who swims to the end of the pool, and then back to the start. According to the math, they didn't go anywhere...
But they did.
Use what ever formulas you like, and what ever units of measure you want. Its still only a description of observed real world results.
I'd venture a guess there are a lot of dead people who would argue that point, if they could...
I do believe firmly that handguns have knockdown power. Large frame steel ones have the most. Hit someone in the head with 3+ pounds of steel and they get knocked down!
But they did.
Use what ever formulas you like, and what ever units of measure you want. Its still only a description of observed real world results.
I'd venture a guess there are a lot of dead people who would argue that point, if they could...
I do believe firmly that handguns have knockdown power. Large frame steel ones have the most. Hit someone in the head with 3+ pounds of steel and they get knocked down!
Micahweeks
New member
I think they only lack in power when compared to rifles and shotguns. As for accomplish the rather simple task of stopping an aggressor, what power they bring to the table is more than adequate. If my revolver can knock down a black bear in one, well-placed shot, it's fine for stopping a home invader. I've never bought into this idea that I need close to rifle or shotgun performance for my handgun to do its job.
Hunter Customs
New member
I don't believe the 270 to be more deadly then the 44 mag at close range, I've seen deer shot with both cartridges and the deer were dead, none were more dead then the others.
It's true the 270 shows more energy, velocity and has higher SD bullets which is all great for longer range shooting, but at close range how much energy and velocity was used in it's intended target and how much was lost once it passes through it's intended target?
Now if I was hunting dangerous game especially where I thought the encounter may be at close range I would choose a cartridge with a much higher KO then either the 44 mag or 270.
Now for self defense against another human at normal self defense distances I would say either the 270 or 44 mag would suffice, however it would be more likely that I would be packing a 44 mag on me then a 270.
Yep, I'll admit, I'm old school, when it comes to packing a handgun I don't buy into all the hype about light bullets and high velocity.
So in most cases when packing a handgun for self defense any caliber that starts with a 4 and ends with a 4 or 5 is my first choice.
Best Regards
Bob Hunter
www.huntercustoms.com
Well when they're dead you can't really tell which one is 'more dead'
That's not really what I was getting at. You can kill a deer with .22LR if you shoot it in the right spot in a hunting scenario. So that's like putting .44mag .270 win and .22LR on equal grounds because they can all kill a deer, and a .44 mag doesn't kill a deer more 'dead' than .22LR either, right?
Suppose you gut shot that deer hypothetically. (remember this is a panic SD situation, maybe you don't get perfect shot placement on the BG, either)
Which one is more likely to take the deer down faster with equal shot placement? A gut shot with 44 mag or .270? The .270 could potentially, destroy the heart and/or lungs even if they're not directly in the path of the bullet. The .44 has much less of a chance to do that. Obviously I don't condone making up for terrible shots, with more gun, but with SD scenario, you are not going to have the same amount of time, to ready your shot, like you would a deer. It's likely that you're going for COM hits and I'd much prefer a rifle round like the .270 over the .44 because of it's remote wounding capabilities which are significantly greater of that of the .44 mag's.
With the right bullet, still more energy than the .44 mag is capable of producing at the muzzle. There are .270 bullets that will get lodged in the far side of the deer, and there are also choices that will pop right out and exit quickly. Don't assume that because the cartridge generates more energy, that a majority of it is 'wasted' because it caused a pass through. You can still dump major energy with a through and through with the right bullet, and as I've mentioned there are choices that will not exit a deer at close range. This argument isn't about bullet selection though, so I digress. My point is with properly selected bullets for both .270 and .44 mag the .270 is capable of far more terminal damage than the .44 yet the .44 has a higher TKO factor, which obviously shows it isn't directly related to power or killing ability.
I think the biggest problem with the TKO factor is that it generally does not factor in a bullet's ability to expand. So essentially the TKO factor is that of a FMJ or wadcutter type bullet. I would think if a .277 bullet expanded to .54 3'' into the target that the TKO factor would vary greatly from the original diameter. Suppose that a .277cal 130 grain bullet @ 3100fps. TKO is 16 before bullet expansion. But what if 3'' into the target the bullet has expanded to .54 caliber and is still traveling 2700fps. TKO is now 27 after 3'' into the target because diameter is larger. TKO favors big bore calibers. It makes .45ACP look comparable to .260 Remington which is just silly to me.
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Tactical Jackalope
New member
Brian hasn't just hit the nail on the head but he's already firmly planted several nails in the wood. I agree 110% pretty much what I was going to say, just a lot more words.
Bob, you don't think my 127gr +P+ 9mm winchester ranger t-series will do as much or even more damage than a .40S&W or .45ACP?
Bob, you don't think my 127gr +P+ 9mm winchester ranger t-series will do as much or even more damage than a .40S&W or .45ACP?
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Whether I've seen it or not. Do you REALLY think that it has more wound potential than a 90 grain SP/HP @ 3600fps, 130 grain SP/HP bullet @ 3000-3200fps or a 150 grain SP @ 2800-2900fps, etc. in .277cal?
I don't see what you're getting at. I never claimed the .44 mag was weak.
Tactical Jackalope
New member
I have. He took his own life. We smelled him from outside his home. I can go into detail if the mods want me to.
Brian Pfleuger
Moderator Emeritus
44AMP said:
Ah... Xeno's Paradox.... in a manner of speaking... the solution to which required the invention of calculus.
If you think these equations are fun, we haven't even touched differential equations or linear algebra.
JD0x0 said:
The kicker there (pun intended
) is that we have to define those words, "power" and "killing ability".We obviously don't mean the physics definition of power, which would be energy consumed over time (watts or joules). Do you mean momentum? TKO is heavily influenced by momentum.
The formula for TKO factor is:
m is mass, v is velocity, d is bullet diameter and 700 is grains per pound.
Essentially, it is the momentum times the diameter, divided by grains per pound.
We have to remember that the TKOf is not a physics formula. It is literally one man's opinion of what made for a lot of knock-out power.
A bullet of 1/2 the diameter, says a .223Rem versus a .45 colt, would have to have some combination of twice as much velocity and mass in order to get to the same TKOf. Considering that cutting the diameter also cuts the mass, pretty much by default unless the bullet gets longer and longer, you need to make up for that with ever increasing velocity.
In other words, Taylor intentionally (and arbitrarily) significantly emphasizes bullet diameter and provides no real rationale for his arbitrary selections, besides the fact that his information is now nearly 75 years out of date.
Hunter Customs
New member
I believe this thread was dealing with knockdown, stopping or Knockout factor, not wound potential.
JD0X0 lets take the coveted 270 that you have been using with another example, seeing that you think KO is not a factor and velocity and energy are the true factors.
Lets say you are heading to big bear country where the shots will be close, you have a choice between a 270 shooting a 130gr Trophy Bonded bullet at a velocity 3050fps producing a muzzle energy of 2685 ft lbs with a KO factor of 15.69 or you can take a 45-70 shooting a 300gr Trophy Bonded bullet at a muzzle velocity of 1850fps producing a muzzle energy of 2280 ft lbs with a KO factor of 36.3, which would you choose to defend your life against a big bear?
Best Regards
Bob Hunter
www.huntercustoms.com
Brian Pfleuger
Moderator Emeritus
Hunter Customs said:
Technically, the thread was supposed to be about "stopping power" as it relates to penetration. I suspect we're a long ways from that, though.
Taylor's KO dealt with shooting big, heavy bullets at huge, dangerous game. He biased his results toward the big, heavy bullets that are (were, 75 years ago) required to get adequate penetration on those huge, dangerous animals.
He was also using bullet technology from the 1940s.
If I had to defend my life against a charging bear, high-momentum, high-recoiling, difficult and slow follow-up shot gun would not be my choice. I do not want a .45-70. Perhaps, if I were extremely well practiced professional hunter, I might take huge .500 Express double rifle or something.
Otherwise, I would choose a relatively low-recoil, semi-auto rifle, with a red dot sight, shooting Barnes TTSX or Hornady GMX bullets as fast as I could drive them and not blow up the gun.
One of the frequently asked questions is what's best for bear defense....
Which is quite a different matter than bear hunting. Although some hunting might combine the two.....
"stopping power" against a human involves human (or nominally anyway) intelligence. Some attacks are stopped by the mere sight of a gun. Some are stopped when the attacker is not critically wounded. Other are only stopped when the attacker is physically rendered incapable of attack, and animal attacks are often in this class as well.
Virtually everyone agrees that if you hit the right spot, with nearly anything, it shuts off man or beast. Everything we discuss when it comes to stopping power, or knock down, or call it what you will, its all about what works better/best and to what degree, when you don't hit just the right spot.
silvermane_1
New member
the whole stopping power/knockdown power arguments remind me of the old B&W film clips of the fat guy getting shot in the gut with a cannon ball.
Hunter Customs
New member
True it's not a physics formula, it's one man's opinion with a lot of real world experience.
That packs more weight then a physics formula with me.
Bullet diameter should be part of the equation, I see no good reason why it should not.
I don't feel that just because his information took place 75 years ago that it's out of date.
Just because something happened years ago does not mean it's not useful today, after all we are still using gun powder.
Best Regards
Bob Hunter
www.huntercustoms.com
Brian Pfleuger
Moderator Emeritus
Yes, I see it like this...
1)I probably won't hit what I need to the first time.
2)I've seen modern, monolithic rifle bullets from "weak" calibers like .243 and 7-08 penetrate deer almost all the way *length wise*.
3) Bears really aren't any different than deer, unless you hit something HARD like the skull or shoulder. If you do that, it's a mute point because you've accomplished your mission (or most of it). I'm going to keep shooting any way until the thing stops twitching. I expect to be scared.
4)Nothing from a 22 short to a .50BMG is going to "knock down" or "stop" the bear unless it hits a vital structure.
So, what I want is not some hard to shoot round that kicks too hard and makes follow-up difficult. I want something that's making a lot of holes as quick as I can make them.
I'd rather have a full-auto .223 built for low recoil, loaded with TTSX than a .45-70 anything. You can have your one, or two if you're lucky, .45 caliber holes. I'll take my chances with 30 .223 holes.
Maybe if I was trained for it I'd choose something else. With no training, dropped into your scenario, I don't want an elephant gun that gives me one chance to get it right.
Besides all that, we are in the handgun forum and none of this "What rifle to stop a bear" really has the slightest relation to the forum or the OP.
Handguns of any nature do not have knock down power of any kind, stopping power is not the same as penetration and, all else being equal, bigger holes are better. Unfortunately, all else is never, ever, equal.
Hunter Customs said:
The whole world, everything in the Universe from Quarks to Galaxies, operates by the laws of physics. Whatever you believe this man's experience was, it was all based on physics, whether or not he knew it or interpreted it correctly.
Hunter Customs said:
The trouble is not that it arbitrarily happened too long ago, it's that things have changed and the formula has not. If it were a physics formula, it would not need to change. Because it is no more than one man's arbitrary creation, it may well need to change and, in fact, may well have no validity at all 75 years later, if it ever did anyway. We can't really know, because it's just one man's idea.
Bullets are not what they were 75 years ago. In most cases, the bargain basement bullets of today are superior to the best you could buy in the 1940s.
I agree that bullet diameter should be *part of* the equation but why PURELY diameter and why multiply momentum and diameter? (Because it gave the result he wanted, that's why)
What about sectional density?
Why momentum and not Kinetic Energy? Why not a formula that considers both?
Why does he arbitrarily divide by 7000? The answers would have exactly the same ratio without being divided by anything. Why not divide by 10,000, or 5,000 or 2,500? Why divide by anything at all?
Why does it not consider expanding bullets? (because the formula only applies to dangerous game where they did not and do not use expanding bullets and is really quite irrelevant to any other scenario)
Those are the problems, it's not because it just expired after 75 years, it's that it failed to adapt (and not being a "law" it may need to adapt), and it really only applies (was ever meant to apply) to specific and dangerous animals/situations.
Also note, that if you believe that TKOf is an accurate formula, you'd be better off defending yourself with a baseball than with a rifle of any kind.
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Hunter Customs
New member
I would have to disagree with this, bears are a lot different then deer.
Muscle fiber, muscle mass, bone density on a bear is a lot different then on a deer.
I'll take the 45-70, even with training a full auto 223 is not that easy to keep on target.
I seriously doubt you will get 30 hits with a full auto 223.
Yes, but there's handguns out there that are capable of stopping a bear, 454 Casull, 475 Linebaugh , 500 Linebaugh even a 44 magnum with the right loads to name a few.
Best Regards
Bob Hunter
www.huntercustoms.com
Brian Pfleuger
Moderator Emeritus
And that's the first time they've been mentioned.
By the way...
"Ruger Only" .45-70 load with 300gr bullet at 2,355fps rated at TKO 52
Major League baseball, thrown 75mph, rated at TKO 108
Which one is better for a charging bear?
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