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I found it interesting that a 30.06 (.308) Federal Powershock 220 gr Speer has almost the same exact velocity as a 35 rem 220gr
Buffalo Bore if both are fired from the 18 1/2" barrel listed at BB's website. The 35 rem Has a higher TKO than the 30.06 (24 -vs- 21).
 

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Bob Shultz said:
I found it interesting that a 30.06 (.308) Federal Powershock 220 gr Speer has almost the same exact velocity as a 35 rem 220gr
Buffalo Bore if both are fired from the 18 1/2" barrel listed at BB's website. The 35 rem Has a higher TKO than the 30.06 (24 -vs- 21).
Is this a range specific figure? :eek: I would think at the longer ranges the larger 30-06 casing (re; larger load) would allow for better performance at greater ranges.

CJ
 

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"range specific"

I'd think, probably not. My calculation is based on factory listed velocities. The ballistic coefficient's aren't that far from each other to make a difference at what I would consider an effective range of inside 200 yards. If I were personally shooting at something with the 220 grain it would be at a distance of around 150 yards or less. Sometimes I compare cartridges where one is thought to be ballistically superior and I run the numbers only to be suprised on occassion. I guess its all relative. I'm a fan of the .35X caliber series. I would like to see what Buffalo Bore or Hornady could do with a 150 grain 35 remington.
 

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Remington JSP 220 grain 30-06 has a MV of 2410'/sec and a BC of 0.294 from a ~24" barrel so yep it looks like the same velocity, too.

BB 35 Remington 220 grain JFN has a MV of 2200'/sec and a BC of 0.316

TKO is based on the impact velocity so it does change with range.
 

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Ive got two of his books,And Im a big fan of the 35. But I think there flaws in that system and ol John at times ;)
 

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So it would seem that within average levergun hunting range the 35 is as effective as the 30.06.
 

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My experience tells me that the .35s are more effective than any '06 round at any reasonable ranges. And, when you talk the same size case, as with the .35 Whelen/200gr, it's head and shoulders above it's parent.
 

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Resurrecting a long-dead thread...

Taylor does tend to favor heavier, fatter bullets.

Taylor KO on heavy 45-70 ammo (heavier than 405 gr), like Beartooth Bullets, Garret, Buffalo Bore, Laser Cast, etc...is right at 50.

Matter of fact, the calculator at handloads.com favors a 525 gr Piledriver at 1500 fps over a 300 gr .375 at 2500 fps by a fairly wide margin: 51 vs 40

A standard 404 Jeffery load of 400 gr at 2200 fps comes in at 53 on TKO, just barely above 525 gr Piledriver.
 

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Not much of a numbers guy, get enough of it on the job. The number that matters is the meplat, where bigger is better. My experience has been that the trauma experienced by a deer is much greater when hit by a 45 cal rifle bullet than a 44, or a 35, or a 30 cal. The trade off is distance -- blunt nosed bullets shed velocity way more than pointy ones, which somewhat limits the distance that a person can accurately hit the intended target.
 

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If you are withing say 100 yards anything with a tko of 40 or better will kill anything on this planet.
 

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I read "African Rifles and Cartridges" By John 'Pondoro' Taylor. If you read his book, you'll see he admits his 'TKO' chart is only theory. Remember, Walter 'Karamojo' Bell parked over a thousand African elephants with a 7X57 and FMJ milsurp ammo.
 

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The Taylor TKO formulas are basically derived from TAylor wetting his finger, holding it up in the air and coming up with a complex formula that he thought would apply better than what was then the Kinetic Energy comparisons. Also solids were used a lot in Taylors world. Whether he is right or not is open to debate, but the numbers are a general guideline and not something to look at as some fine differences. The old 303 British was used around the world and killed about anything worth killing with the old 215 grain loads. The Canadians on one website were complaining about Remington dropping the old Core Lok 215 grain load. These loads were less than the 30-06 220 grain loads which also have been used in North America on about anything. The extra .050 inch of bore diameter does not make for any great differences in killing power and actually offer less downrange performance than the 30 calibers with a similar weight bullet. A round nose 30 cal still holds up pretty well down range but the 35 loses velocity pretty quick. With soft points the advantages of bore diameter shrink a bit. Actually the 30 cal probably penetrate a little more.

I have a 35 Remington and like it on deer. I shot a deer with a cast 303 208 grain bullet and I can say that based on that small sample the 35 has no advantage. I bought the 35 because I was using heavy bullets in the 30-30 and liked them. After getting the 35 I did not need to go through the hassle of using the 30-30 cast bullet loads. I think as stated TAylors formulas are very general and small differences in results are to be ignored. One reason Rourke wrote his book "Use Enough Gun" because he saw how abysmally the 220 Swift performed on larger game that the high velocity disciples were swearing by.

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John Taylor was an elephant hunter, and this formula was his attempt to compare various large bore calibers according to his observations in the field. By using his formula, according to him, it was possible to predict the amount of time an elephant would be knocked out after a near miss on a brain shot. Taylor was market hunting for ivory and often took rapid brain shots at several elephants in a group, or had to make stopping shots at charging Jumbo. He wanted the insurance of stopping an animal, at least for a little while, with a suboptimal shot placement. With the elephant/elephants on the ground, and if he were still alive, he could then apply the coup de grace.

For example, he predicted that a near miss brain shot from a .416 Rigby would momentarily stun an elephant, while a .470 Nitro Express would knock out an identical elephant for up to 5 minutes. Knock out times increased with large rounds and calibers until he predicted 25 minutes for the .577 NE and 30 minutes for the .600 NE. This method was Taylor's attempt to reconcile similar bullet velocities, similar bullet weights, but differing bullet diameters with his observations. He did not test all these rounds on elephants.

Understand that it is not possible to reproduce one ideal elephant for testing with multiple calibers, nor is it possible to reproduce the exact same near miss to a brain shot from animal to animal. His hypothesis is untestable and his formula is a construct.

While it is an interesting exercise to apply the Taylor KO formula to the .35 Rem and the .30-06, this misses the point, unless you are planning to just miss brain shots on elephants. It bears no relation to the merits or effects of these two calibers for either good or bad shots on large bears or moose, for instance, nor for deer or hogs.

Taylor did not do a comparative study to compile his formula, but rather, he wrote a formula to support his opinions on the attributes of the cartridges he preferred. His formula primarily emphasizes the effect of diameter (bullet frontal area), then bullet weight, then velocity.

For the calibers Taylor mentions, say .30 and larger, the effect of any of these on a medium sized antelope through the shoulder or into the heart, in other words good shot placement, would likely be dead right there.
 

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Increase chamber pressure far enough, and nearly any cartridge can be 'nearly identical' to something else at a cherry-picked data point.

Buffalo Bore's .35 Rem 220 gr load cannot leave a 18.5" barrel at 2,200 fps without exceeding SAAMI MAP. It is a +P load.
The .30-06 load being compared, however, is running at or below SAAMI MAP.

Increase the .30-06 chamber pressure by the same amount as the BB .35 Rem load, and you have to go looking for a new data point to cherry-pick, because the previous 'nearly identical' or 'even better' is going to disappear.


I can get the trajectories to match with my .30-06 and .444 Marlin, or '06 and .35 Whelen. 'Almost perfectly identical'...
But the '06 has to be downloaded to 43-48k psi and the 444 has to be hot-rodded to 65k psi with a special bullet (in a single-shot, only!); or the '06 has to be loaded with a low BC bullet, with the Whelen pushing a heavier bullet with a reasonably decent BC.
They're almost perfectly identical ... but no longer really operating as designed.
We can bend the rules all we want for hypotheticals and to try to justify a certain cartridge being King of the World, but, in the end, we're really doing nothing more that taking one or more of the cartridges out of their comfort zone and trying to ignore the fact that different cartridges do things differently (with some influence from the rifle).

I like big, heavy, and slow.
But I also enjoy small, light, and fast.
Each has its place. Each can be used quite effectively when properly chosen and applied.
 

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Bullet kinetic energy is determined by the velocity and the velocity component is squared, basically E=MV² or energy-= mass(bullet weight) x velocity². It favors velocity and favors higher velocities even more. So, a .264 Win Mag with a super fast light bullet gets a big boost in calculated energy while a 45-70 with a 400 grain low velocity bullet gets little help from velocity in the kenetic energy calculation. It gives us a point of reverence for generalizations like "you need to have 1500 ft-lbs energy at the target for elk and 100 ft-lbs for deer". Nice as those generalizations are they become less and less relevant as you increase bullet mass and diameter.

For a long time many people have recognized the need for a more useful way to predict and compare performance of various bullets on game. The key to most of them involves including some sort of allowance for a bullet's momentum. The basic formula is P= MV, where P is momentum, M is mass, and V is velocity. As you can see, in calculating momentum velocity is not squared and therefore, unlike kinetic energy calculations, the mass of a bullet plays a larger part in the end calculation.

A classic example illustrating the need to consider momentum in predicting bullet effect on game involves comparing the impact of an aspirin to the impact of a canon ball. A 15 lb canon ball (105,000 grains) going 100 fps and a 300 mg aspirin (4.63 grains) going 15,050 fps have the same kinetic energy but the effect of each on an elephant would be very, very different. Even though the canon ball is going 150.5 times the velocity of the aspirin it has a whopping 22, 678 times the aspirin's mass, meaning the canon ball will have 150 times the momentum.

However, the very example above begs all sorts of questions. Primarily, in the extreme, it can over-account for mass in very, very heavy bullets. Imagine the difference in momentum between a needle in flight and a rolling freight train. Velocity and kinetic energy still should be part of the final equation but there is more to consider. Another problem is that neither a kinetic energy formula nor a momentum formula take into account the cross sectional density of the bullet. We know in general that bullets of greater sectional density apply more force per area of the bullet "face", will tend to penetrate more and are better at punching through thick hide and heavy bone, all else being equal.

Taylor was an elephant and dangerous game hunter. He was looking for a tool to predict "stopping power" of bullets on elephant and noted the shortcomings of both the kinetic energy and momentum formulas when used alone. He knew that both should play an important role in arriving at a formula to predict stopping power. So, he used both and added to it a computation accounting for differences in sectional density. He came up with a preliminary formula. Then he compared calculated results for many bullets and calibers to actual field results. He noted irregularities between calculated and observed data then reworked his formula until the predicted results seemed to coincide with the field results. He called it a "power yardstick", a formula for predicting the "knock-out factor" of a cartridge.

Today, Taylor's yardstick is commonly referred to as the Taylor Knock-Out Factor or simply TKOF or TKO. It's not a perfect tool. One thing still missing is a way to factor in bullet construction. For example, a solid non-expanding bullet versus a fast expanding hollow point bullet. But nothing is perfect. In my opinion, it is the most useful tool for comparing effectiveness of cartridges and bullets on a big game animals.

Here is a link to an online TKO calculator: Taylor KO Calculator | Energy | Momentum | Bullet

For example, TKO using the calculator:

350gr .45-70 bullet with impact velocity of 1700 fps = 39
150gr .30-06 bullet with impact velocity of 2700 fps = 17
140gr .264 WinMag with impact velocity of 3200 fps = 16
200gr 10mm auto bullet impact velocity of 1100 fps = 12

You get the idea.
 

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Remington JSP 220 grain 30-06 has a MV of 2410'/sec and a BC of 0.294 from a ~24" barrel so yep it looks like the same velocity, too.

BB 35 Remington 220 grain JFN has a MV of 2200'/sec and a BC of 0.316

TKO is based on the impact velocity so it does change with range.
I have had at least 6 336`s in 35 Rem including an A with a 24" barrel.I could not hit 2,200FPS with a 200 grain bullet and would have to see the 220 do 2,200FPS for myself to believe that.Just sayin,OB
 

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Ed Lowrey was a ballistics engineer working for Winchester that wrote articles for the National Rifleman. He often wrote on shotguns and birdshot ballistics. He came up with a formula that is used in a modern computer program for birdshot ballistics but in his article talked about everything up to cannon ball. Basically he found penetration was better computed using sectional density in place of mass in the formula for momentum in the formula Grenadier mentioned. Also velocity for penetration was based on the velocity of impact-threshold velocity. Threshold velocity being that velocity in which penetration starts instead of the projectile bouncing off. Another variable in the formula was the coefficient of permeability. The same formula could be applied to rifle bullets if they were solids (birdshot does not really expand). A heavier bullet of the same caliber has a higher SD which will permit it to penetrate more. A larger caliber bullet of the same weight does not penetrate as much if going at the same speed. Coefficient of permeability for armor plate is 0 so you get no penetration. The formula is only good for prediction in ballistic gel.

Basically the mathematical formulas that have been used are unidimensional in that they only measure one factor of effectiveness. Also as has been brought out here, the issue of the animal being shot has to enter in. Jack O Connor lent his 416 Rigby to a guide so he could shoot a deer with an "elephant gun" O Connor stated that the damage was not as excessive as some would have thought and not so much as a good 270 load. That 350 grain 45-70 bullet at 39 probably would not do as much damage on a deer as the 150 grain 06 bullet at 17. On a moose it might be better. A deer with a heightened adrenaline level will run farther after getting shot than one totally unaware. Most choices for a rifle can be made more as a comparison to the proven ones. I have experience with the 303 British and 300 Savage. I would suggest that the 307 Winchester or 308 Marlin probably would be very similar in performance.

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