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I am going to introduce you guys to the reason why I harp on .44's and .45's so much here. Nothing wrong with a .357 or 9MM that a couple more rounds on target won't cure. But Bullet/Boolit Diameter does matter.
In order to Quantify that for you we use a Century Old formula called the Taylor Knockout Factor or TKO for short. It was invented by a Great White Hunter named John "Pondoro" Taylor(1904-1969) He killed literally thousands of African Big Game animals and thus became an expert on the subject of larger caliber rifles and like Elmer Keith became accepted as "One Who Knows!"
The Taylor Knock Out Formula is,,, Bullet Diameter X Bullet Weight in Grains X Velocity / 7000
This will yield a "number" (TKO) which will be used to compare to other bullets.
Here's a link to a nifty Calculator https://www.vcalc.com/wiki/taylor-knock-out-factor
It effectively shows how a larger diameter bullet transfers more of it's energy to a target than a Smaller Faster bullet does, and even though the Smaller Bullet may have more Ft/Lbs. of energy, it can't transfer that energy to the target as efficiently as the larger bullet.
Lets compare a few bullets so you can see what is going on here.
.357 Mag to .44 Mag in a Pistol..
.358 x 158 x 1500 / 7000 =TKO 12.1
.429 x 250 x 1300/ 7000 = TKO 19.9
Not that big a difference? Lets Jack Up the Speed to Rifle Velocity's.
.357 @ 1900 = TKO 14.5,,, .44 @ 1800 = TKO 27.6 almost double.
I can easily get 1800 fps out of my 1894CB 24 .44 Mag.
Now for reference .30-30 WCF .308 x 170 x 2000 = TKO 15.0
So a .357 from a Rifle is close to having as much knockdown power as a .30-30? Even though the .30-30 has 1510 Ft/Lbs and the .357 only has 1266 ft/lbs.
Lets go up to a .45-70 405 gr Boolit at 1800 fps,,, TKO 47.7 / 2913 Ft/Lbs
.458 Win Mag 500 gr bullet at 2150 fps TKO 70.3 / 5131 ft/lbs
12 ga. 1oz Slug at 1600 fps. TKO 71.2 / 2427 Ft/lbs ?
So how can a 12 ga. Slug from a $300 Shotgun have more TKO than a .458 Win Mag with only half the Ft/lbs? Simple, the .458 Bullet goes all the way thru the animal and buries itself in the dirt beyond, effectively only delivering enough Ft/Lbs to the animal to get thru said animal. Whereas the Shotgun Slug dumps all it's energy into the animal on contact due to the larger Frontal Area of the Slug. The Frontal Area of the Slug is .418 Sq In. vs .164 Sq In for the .458 bullet. Or close to 3 X the Frontal Area for the slug.
This is why all the Polar Bear Guides up North carry Shotguns with Brenneke Slugs as back up weapons for their clients instead of large caliber rifles..
This is also the sole reason for Expanding Bullets,,, (which may or may not work as advertised),,, in an attempt to dump all the energy into the target?
Larger Boolits don't rely on "Engineering" or "Specific Velocity Ranges" to perform, they simply make bigger holes and due to their larger "Frontal Area" transfer more energy to the target.
It should be noted when talking about "Powerful Guns" that Brenneke makes a 1 1/2 oz. slug, traveling at 1604 fps with a TKO of 109!!! with 3800 Ft/Lbs of energy. It will take down anything on Planet Earth and if I was man enough to pull the trigger I could shoot them from one of my Mossberg 500's. (only once.) Might be more doable from a Savage 212? But either way it would be brutal!
So I base my assertions of Proper Handgun Calibers all starting with a .4 on the TKO of any given load and the simple fact that bigger boolits make bigger holes!
Hope this helps with understanding of the subject?
Randy
In order to Quantify that for you we use a Century Old formula called the Taylor Knockout Factor or TKO for short. It was invented by a Great White Hunter named John "Pondoro" Taylor(1904-1969) He killed literally thousands of African Big Game animals and thus became an expert on the subject of larger caliber rifles and like Elmer Keith became accepted as "One Who Knows!"
The Taylor Knock Out Formula is,,, Bullet Diameter X Bullet Weight in Grains X Velocity / 7000
This will yield a "number" (TKO) which will be used to compare to other bullets.
Here's a link to a nifty Calculator https://www.vcalc.com/wiki/taylor-knock-out-factor
It effectively shows how a larger diameter bullet transfers more of it's energy to a target than a Smaller Faster bullet does, and even though the Smaller Bullet may have more Ft/Lbs. of energy, it can't transfer that energy to the target as efficiently as the larger bullet.
Lets compare a few bullets so you can see what is going on here.
.357 Mag to .44 Mag in a Pistol..
.358 x 158 x 1500 / 7000 =TKO 12.1
.429 x 250 x 1300/ 7000 = TKO 19.9
Not that big a difference? Lets Jack Up the Speed to Rifle Velocity's.
.357 @ 1900 = TKO 14.5,,, .44 @ 1800 = TKO 27.6 almost double.
I can easily get 1800 fps out of my 1894CB 24 .44 Mag.
Now for reference .30-30 WCF .308 x 170 x 2000 = TKO 15.0
So a .357 from a Rifle is close to having as much knockdown power as a .30-30? Even though the .30-30 has 1510 Ft/Lbs and the .357 only has 1266 ft/lbs.
Lets go up to a .45-70 405 gr Boolit at 1800 fps,,, TKO 47.7 / 2913 Ft/Lbs
.458 Win Mag 500 gr bullet at 2150 fps TKO 70.3 / 5131 ft/lbs
12 ga. 1oz Slug at 1600 fps. TKO 71.2 / 2427 Ft/lbs ?
So how can a 12 ga. Slug from a $300 Shotgun have more TKO than a .458 Win Mag with only half the Ft/lbs? Simple, the .458 Bullet goes all the way thru the animal and buries itself in the dirt beyond, effectively only delivering enough Ft/Lbs to the animal to get thru said animal. Whereas the Shotgun Slug dumps all it's energy into the animal on contact due to the larger Frontal Area of the Slug. The Frontal Area of the Slug is .418 Sq In. vs .164 Sq In for the .458 bullet. Or close to 3 X the Frontal Area for the slug.
This is why all the Polar Bear Guides up North carry Shotguns with Brenneke Slugs as back up weapons for their clients instead of large caliber rifles..
This is also the sole reason for Expanding Bullets,,, (which may or may not work as advertised),,, in an attempt to dump all the energy into the target?
Larger Boolits don't rely on "Engineering" or "Specific Velocity Ranges" to perform, they simply make bigger holes and due to their larger "Frontal Area" transfer more energy to the target.
It should be noted when talking about "Powerful Guns" that Brenneke makes a 1 1/2 oz. slug, traveling at 1604 fps with a TKO of 109!!! with 3800 Ft/Lbs of energy. It will take down anything on Planet Earth and if I was man enough to pull the trigger I could shoot them from one of my Mossberg 500's. (only once.) Might be more doable from a Savage 212? But either way it would be brutal!
So I base my assertions of Proper Handgun Calibers all starting with a .4 on the TKO of any given load and the simple fact that bigger boolits make bigger holes!
Hope this helps with understanding of the subject?
Randy
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