Mr Taylors KO values

norfolk shooter · May 30, 2020

Alright chaps,
I have been wondering just how relevant the KO values are today given the bullets we use are better than back when Taylor came up with his formula?
Also would a round with a KO value of 48 be a good DG round if the shooter has confidence and ca shoot it rather well?

Many thanks as always

NS :D Beer Bottle:

shootist~ · May 30, 2020

9.3x62 0.3660 0.1830 A-Frame 300 2,300 0.385 2,840 0.320 0.105208708 95.6 36.1

According to a spreadsheet I use to track such interesting things, a 9.3x62 with 300 grain bullet at 2,300 fps MV has a Taylor KO of 36.1. (Wt in grains x V x Bullet Diameter) / 7,000. This from the Robertson book...assuming I did it correctly.

If that were considered the minimum for buffalo, then 48 would be well up there. Other than that, I have no idea.

Alistair · May 30, 2020

I should think that in terms of 'KO' factor, bullet quality and construction has little bearing.

As I understand it, Taylor based this formula on imparting energy, ie stunning an elephant with a poorly placed head shot, not on consistent penetration (hence why BC or penetration depth is not included in the formula).

Actually, as far as this formula is concerned, the bullet is assumed to dump all of it's energy into the animal in an area the size of the frontal cross section of the calibre, presumably imparting some kind of hydrostatic shock effect that 'knocks down' the animal either via hydrostatic shock or concussion. Interestingly, the only bullet that would actually do this is reality is an extremely frangible one which 'fails', blowing up on impact and not exiting the animal. Better penetration, if the bullet leaves the animal, simply means that the 'KO energy' is not imparted effectively and is wasted, retained in the projectile flying into the ether.

As for a KO value of 48, that's what, .404Jeff ish? That, a very hot 375 or a very mild .416. I'd back any of those 3 calibres!

Al.

Red Leg · May 30, 2020

I find Taylor's analysis a fascinating historical work.

norfolk shooter · May 31, 2020

Alistair said:
I should think that in terms of 'KO' factor, bullet quality and construction has little bearing.

As I understand it, Taylor based this formula on imparting energy, ie stunning an elephant with a poorly placed head shot, not on consistent penetration (hence why BC or penetration depth is not included in the formula).

Actually, as far as this formula is concerned, the bullet is assumed to dump all of it's energy into the animal in an area the size of the frontal cross section of the calibre, presumably imparting some kind of hydrostatic shock effect that 'knocks down' the animal either via hydrostatic shock or concussion. Interestingly, the only bullet that would actually do this is reality is an extremely frangible one which 'fails', blowing up on impact and not exiting the animal. Better penetration, if the bullet leaves the animal, simply means that the 'KO energy' is not imparted effectively and is wasted, retained in the projectile flying into the ether.

As for a KO value of 48, that's what, .404Jeff ish? That, a very hot 375 or a very mild .416. I'd back any of those 3 calibres!

Al.

Al the figure of 48 is in fact from a mild 416 Rigby load. It seems to group rather well. The moment I go up 5-6 grns the groups open up like a cheap birds legs mate

Ridgewalker · May 31, 2020

Like all calculations, you must test to prove it. I think you need to go on an all DG hunt to validate the 48 KO theory! Maybe elephant, Cape buffalo, hippo and with soft bullets, lion and leopard. I’ll be watching to see your results!

Alistair · May 31, 2020

norfolk shooter said:
Al the figure of 48 is in fact from a mild 416 Rigby load. It seems to group rather well. The moment I go up 5-6 grns the groups open up like a cheap birds legs mate

A 400gr at 2,000 by any chance?

norfolk shooter · May 31, 2020

Ridgewalker said:
Like all calculations, you must test to prove it. I think you need to go on an all DG hunt to validate the 48 KO theory! Maybe elephant, Cape buffalo, hippo and with soft bullets, lion and leopard. I’ll be watching to see your results!

Would a muntjac deer count?

norfolk shooter · May 31, 2020

Alistair said:
A 400gr at 2,000 by any chance?

Your VERY close!! 2035. Im going to play with the load a little the odd grain or 2 up and down

Mr Taylors KO values

norfolk shooter

shootist~

Alistair

Red Leg

norfolk shooter

Ridgewalker

Alistair

norfolk shooter

norfolk shooter

Members online

Forum statistics

Proudly sponsored by

Latest posts

Latest profile posts

Buffalo Hunt with Henry Griffiths Safaris $10000

Share this page