Energy delivered "to the animal" from a projectile

[Art Caputo]

I would start with the premise that there is no substitute for shot placement. I very much prefer total penetration.....two holes. Each animal can react differently to a well placed, fatal shot. Two holes will provide a better blood trail if needed, and can allow disabling air to enter the body cavity...should the animal “run” at the shot. IMO, deer are rarely killed by “hydrostatic shock” with typical muzzle loader loads. Bone(and fragment projectiles) and tissue damage is what kills. Generally, the larger, heavier, and faster the ball at point of impact, the more damage. I have had cases when a close range 45 cal ball driven at high velocity(+2000FPS) expanded to the point where it came apart, and didn’t fully penetrate....but did inflict major internal damage. Regardless of the initial muzzle velocity, the roundball sheds velocity very quickly. Smaller, lighter round balls due to the lighter weight and lower ballistic coefficient will shed velocity faster then a larger heavier ball. Initial velocity differences between smaller and larger round balls of 300-400FPS will be within 100-200 FPS of each other by the time they reach 100 yards. In this case, the larger and heavier ball can inflict more damage with the same shot. I personally prefer to use Taylor’s Knock-Out formula to determine point of impact energy comparisons over the conventional formula used to calculate energy at the target. While this formal was originally designed by a John Taylor for the specific purpose of knocking an elephant out with a head shot using solids, IMO, it give a better reflection of killing power using round balls/conicals since the formula places “greater” emphasis on the diameter and weight of the bullet, and less on velocity. I think that this premise is relevant when using round balls and conicals on larger game. While this is surely not a scientific study, it has better correlated with my experience on game over the past few decades. I’m mostly concerned with the TKO value at the distance game which is taken as opposed to the muzzle. I have found a minimum value of “10” to be my preference on whitetails and similar sized game. The formula is a follows:

[(diameter/inches) x (weight/grains) x (velocity/FPS)] / 7000(constant)= TKO Value

Example for my 50 cal at 100 yards. [.490” x 178 grains x 1025FPS] / 7000 = 12.8 TKO@ 100 yards

Shown a few of my rifles comparing the conventional formula of energy with the TKO formula at the muzzle and 100 yards.

 

[rodwha]

I would start with the premise that there is no substitute for shot placement. I very much prefer total penetration.....two holes. Each animal can react differently to a well placed, fatal shot. Two holes will provide a better blood trail if needed, and can allow disabling air to enter the body cavity...should the animal “run” at the shot. IMO, deer are rarely killed by “hydrostatic shock” with typical muzzle loader loads. Bone(and fragment projectiles) and tissue damage is what kills. Generally, the larger, heavier, and faster the ball at point of impact, the more damage. I have had cases when a close range 45 cal ball driven at high velocity(+2000FPS) expanded to the point where it came apart, and didn’t fully penetrate....but did inflict major internal damage. Regardless of the initial muzzle velocity, the roundball sheds velocity very quickly. Smaller, lighter round balls due to the lighter weight and lower ballistic coefficient will shed velocity faster then a larger heavier ball. Initial velocity differences between smaller and larger round balls of 300-400FPS will be within 100-200 FPS of each other by the time they reach 100 yards. In this case, the larger and heavier ball can inflict more damage with the same shot. I personally prefer to use Taylor’s Knock-Out formula to determine point of impact energy comparisons over the conventional formula used to calculate energy at the target. While this formal was originally designed by a John Taylor for the specific purpose of knocking an elephant out with a head shot using solids, IMO, it give a better reflection of killing power using round balls/conicals since the formula places “greater” emphasis on the diameter and weight of the bullet, and less on velocity. I think that this premise is relevant when using round balls and conicals on larger game. While this is surely not a scientific study, it has better correlated with my experience on game over the past few decades. I’m mostly concerned with the TKO value at the distance game which is taken as opposed to the muzzle. I have found a minimum value of “10” to be my preference on whitetails and similar sized game. The formula is a follows:

[(diameter/inches) x (weight/grains) x (velocity/FPS)] / 7000(constant)= TKO Value

Example for my 50 cal at 100 yards. [.490” x 178 grains x 1025FPS] / 7000 = 12.8 TKO@ 100 yards

Shown a few of my rifles comparing the conventional formula of energy with the TKO formula at the muzzle and 100 yards.
View attachment 47407

I, too, feel the Taylor system to provide a more accurate idea.

 

[Nameless Hunter]

Actually they won’t have exuded the same amount of energy at X point in the animal. We know that the faster a projectile moves the more it pushes out of the way. The damage is greater at X point by the faster projectile IF it is going fast enough. It seems that a ball under 1100 FPS or so just makes a caliber sized hole so the damage might be the same at 1000 FPS as it is at 600, but get that ball moving fast enough and that damage will get greater.

Regardless I don’t buy the “dumped all the energy” stuff. 2 holes leaking is good in my mind.

Just a Scientific W.A.G., but I would hazard that any projectile moving faster than the speed of sound would create some form of a shockwave, which would most likely increase tissue damage.

 

[rodwha]

Just a Scientific W.A.G., but I would hazard that any projectile moving faster than the speed of sound would create some form of a shockwave, which would most likely increase tissue damage.

Indeed it does, and it can also begin to flatten soft lead upon impact which also increases the wound size, but then this seems to be where people will be finding flattened balls on the offside under the hide more often, and this seems to be what those in favor of the complete energy dump tend to stand and not from a perspective of half penetration but still a harvested animal. A ball that can only penetrate half way would be going awfully slow at impact. I’ve seen the old military video showing a ball from an 1860 Army at around 650 FPS or something penetrate through bone imbedded in gel. Not quite sure if it would make it completely through on a side shot, but it looked like it might well.

One could also use a wide meplat, especially if the velocity is rather low. I have 0.375” meplats on my revolver bullets. Even my NMA, which looking at similar loads as mine, will be traveling over 900 but under 1000 FPS with my 195 grn version using a weighed 33-35 grns of 3F Olde Eynsford, which isn’t even a maxed load. According to Beartooth Bullets, makers of wide meplat hunting bullets, shows a 0.370” meplat at 900 FPS creates roughly a 0.833” diameter permanent wound track. I’d take that over a 0.490” ball at the speed of sound since it won’t make but a caliber sized hole and with less mass. Of course I’d use my ROA with the additional 5 grns of powder and 1/2” better groups, and above 1000 FPS giving me about a 0.925” permanent wound track.

 

[Old Hawkeye]

Just a Scientific W.A.G., but I would hazard that any projectile moving faster than the speed of sound would create some form of a shockwave, which would most likely increase tissue damage.

IIRC, for hydrostatic shock to have an effect on lethality or "knock down" power a bullet needs to be going a minimum of 2000 fps, So I'm not sure that the "shockwave" from a ML projectile is much of a factor. In fact, the OP's initial question is almost impossible to answer because of the multitudes of variables that come to play. Two bullets can have the SAME energy, but depending on their construction, velocity, metallurgy, shape, etc., etc., one may pass thru & one may not. So which one is better, the one that stays in the animal or the one that passes thru? Seems to me that can't be answered until one witnesses the result. Boils down to "two hole are better then one" from my point of view.

 

[Nameless Hunter]

IIRC, for hydrostatic shock to have an effect on lethality or "knock down" power a bullet needs to be going a minimum of 2000 fps, So I'm not sure that the "shockwave" from a ML projectile is much of a factor. In fact, the OP's initial question is almost impossible to answer because of the multitudes of variables that come to play. Two bullets can have the SAME energy, but depending on their construction, velocity, metallurgy, shape, etc., etc., one may pass thru & one may not. So which one is better, the one that stays in the animal or the one that passes thru? Seems to me that can't be answered until one witnesses the result. Boils down to "two hole are better then one" from my point of view.

I don't have the testing background to debate about the 2000 fps minimum speed requirement, but I can understand higher velocities creating greater damage. I also have seen the damage caused by a 300 gr hollow pt hitting a deer at 1700 fps - very large exit hole. Maybe it was the hollow pt design of the bullet...

 

[hanshi]

Deer are not killed by some number that's applied to "energy". They are killed by the damage they inflict on the vital organs hit by a well placed shot. It makes no difference to me whether or not the ball is a pass-through. The deer always left a short blood trail that was easy to follow. The most gruesome trail I've seen was a buck I shot with a .45 prb that didn't exit. Although he fell within sight the trail was immediate and awesome. The red was not only on the ground but also on tree trunks & bushes from knee-high to nearly waist level. 100+ yard hits passed through but carried little energy. Still, the hits dropped deer like dominoes just a few yards from where they were hit. A hit from a .308 with a solid bullet carries a huge KE load; but often doesn't kill deer within a retrieval time/distance span.

 

[Tom A Hawk]

Deer are not killed by some number that's applied to "energy". They are killed by the damage they inflict on the vital organs hit by a well placed shot. It makes no difference to me whether or not the ball is a pass-through. The deer always left a short blood trail that was easy to follow. The most gruesome trail I've seen was a buck I shot with a .45 prb that didn't exit. Although he fell within sight the trail was immediate and awesome. The red was not only on the ground but also on tree trunks & bushes from knee-high to nearly waist level. 100+ yard hits passed through but carried little energy. Still, the hits dropped deer like dominoes just a few yards from where they were hit. A hit from a .308 with a solid bullet carries a huge KE load; but often doesn't kill deer within a retrieval time/distance span.

Having killed deer with bow and arrow, I agree with your observations regarding shot placement and tissue damage. I have seen arrow wounds where significantly more damage was done than with any round ball. The bushes were well painted as mentioned. Not so sure about hydrostatic shock not being a factor. My 125 grain .54 Hawken load has rather impressive impact and I've had some instant - in their tracks, drops.

 

[nkbj]

Just a suggestion for everybody.
Do the math on the rate of displacement offered by different caliber round ball diameters operating at various velocities.
It's an eye opener when looked at in the context of known effectiveness on game though it is in no way a do-all-end-all for figuring out what to shoot.
This was a calculation I made when designing cast bullet wildcat cartridges over thirty years ago and have found it to be applicable to round ball.

 

[Okie Hog]

My deer hunting with conventional muzzleloaders is with .50 and .54 caliber rifles using patched round balls. Most deer are shot from tree stands at close range or have been stalked to 50 yards or less. Could care less that the ball exits. About half of my deer are high shoulder shots-DRT. Deer i've shot in the heart-lung area seldom travel more than 50 yards.

 

[Spikebuck]

In fact, the OP's initial question is almost impossible to answer because of the multitudes of variables that come to play.

Actually, my statement, or question if you will, was very limited in variables since only speed was a variable. Same projectile, same path into the animal. Only variable being speed and thus the energy the projectile carried. I intentionally tried to avoid comparisons of X vs Y. My only intent was to express that I don't believe that it's accurate to state that a projectile that stays in the animal is somehow better "because it delivered all it's energy" than one that goes all the way through, assuming same projectile and path.

There has been a lot of good discussion and I think the majority of responders would rather have the longer wound channel and an exit, all other factors equal.

I agree that in hunting, there are so many variables it's hard to always know what exactly might happen. I guess that's also part of the attraction.

Thanks, everyone for your responses.

 

[sussexmuzllodr]

=========D))))))))))))))))))))))))))))))))))0 or something like that.......

 

[rodwha]

This may be of interest:

https://gunstreamer.com/watch/milit...tration-past-and-present_Yb6cmGaaeGDU6jY.html