Bullets deadliness

[j.trevor123]

OKay i have a question. I was told that a bullets energy in foot lbs is how much knock down power a bullet has. But in alot of calibers their is always a smaller caliber with a higher foot per lbs than the larger grain. For example if you are shooting a 150 grain 30-30 powerpoint vs a 170 grain powerpoint which would be more potent? (150:vel-2390,ener-1902.....170: vel-2200 ener-1827 at muzzle. So would that conclude that the 150 is more potent??? So when would u want to use a 170 over 150 if ever??

[sgtt]

If you check the charts further..........I believe that the 170 will carry more energy out yonder where the target is.  I cannot state that unequivocally as I do not have a chart at hand.  The difference is miniscule and I would opt for the bullet which is the most accurate out of my gun.  If you don't hit it, it ain't gonna matter.

[Castaway]

Foot pounds of energy is only a predictor of potential deadliness.    In theory, you could drive a sewing needle to have more foot pounds of energy than a 150 grain bullet launched from a 30-06 but I sure wouldn't hunt with a sewing needle no matter how fast it travels. The Taylor Knock Down Formula is a better forcasting tool.  It is:

TKO value = [ Weight (gr) x Terminal Velocity (fps) x calibre (in) ] รท 7000

This itself is not perfect as it doesn't take into consideration bullet design.  A SWC is better than a round nosed bullet.  Expansion is also a factor, sometimes it's good, sometimes it's bad, depending on how tough the animal is.

[victorcharlie]

One also has to consider momentum, or the ability to resist a change in motion.  One example, is a wiffle ball traveling at 80 mph, hits you in the head, against say a baseball traveling at 40 mph.  If I'm not mistaken, kinetic energy = 1/2 mass X velocity squared.  Momentum is simply mass X velocity.  This has spurned some heated debates, some of the most famous being big bore advocate Elmer Keith and hyper velocity advocate Jack O'Conner.  

Another example, is that a .243 will generate close to the same energy as a .45/70 in a factory load.  However, the .45/70 will certainly penetrate far deeper than the .243.  

So, all things equal, I personally think the larger the cal, the more the mass, the harder the hit.

[Prince of Wales]

Yes paper ballistics can be difficult to explain.
 A 55 gr.30/06 Accelerator on paper will generate more energy than a 45/70.
Which would you rather have at hand in the event of a charging brownie?
 I like paper ballistics but try to remember that they are just a reference. Actual killing power sometimes is another matter. POW

[huntsman]

First of all, bullet energy is NOT supposed to equate to "knock down power" (whatever the latter actually means). It is but one way to look at what a bullet is doing as it travels along its trajectory. There are many other factors involved in how a bullet will PERFORM once it hits a specified target, including qualities of the target itself.

"Stopping power" or "knockdown power" are terms generally used to describe a desired effect of a bullet penetrating a target and then expending maximum energy inside the target, thus causing the target to absorb the full energy of the projectile. Ideally, the bullet would penetrate the target, mushroom to as close to pancake proportions as possible, and stop underneath the skin on the opposite side of a living target.

Foot-pounds of energy will provide a generalized picture of the energy to be expended, but it does not account for many features of the projectile/target interaction that actually occur when a target is hit. The optimum bullet construction and weight for "knockdown power" in a given load often has much more to do with bullet design and velocity/mass ratio than foot-pounds of energy.

Now to your "more potent" question of 150 grain versus 170 grain bullets in the 30-30. Assuming you are going to be shooting at deer or similar animals, you can expect either bullet weight in a flat-nosed design at 30-30 velocities within a 200 yard range to both penetrate the target and exit the target on a broadside shot. The only question now is which one expends the most energy in the target. That will depend on a number of factors, including bullet construction (fragility vs. integrity), whether bone is hit or not (residual damage), and initial versus exit velocity. The equation rapidly becomes too complex for a simple "this bullet is better" conclusion.

Any general conclusion you might come to would be based on a standard set of values for target characteristics, range, and type of bullet. My own experience with the 30-30 for shooting average-sized whitetail deer, in both my hands and those of other hunting companions, is generally the same as with other high-velocity rifle cartridges: lighter bullets of standard or weaker construction will tend to expend more energy inside the target than will heavier bullets of more sturdy construction within the normal shooting range of the caliber (to 150 yards or so). Again, there could be great variation in actual performance based on many factors. This is just a generalization, not a standard principle.

I would also qualify the above statement with the fact that I have never seen a deer shot with any bullet from a 30-30 (not striking the central nervous system) go down "in its tracks". I've seen several that ran several hundred yards, but most went down after a short dash of 30-80 yards. That doesn't mean a knockdown can't happen, but it is my observation that the 30-30 is probably not the best knockdown cartridge out there. The relatively big and slow-moving bullets of the 30-30 tend to penetrate well and kill efficiently, but are not well-suited to the great expansion and rapid deceleration required of the best knockdown cartridges.

[victorcharlie]

Very well said huntsman.  I've killed quite a few deer, and probably 90% have been with an 85 grain .243.  All most all of them have dropped dead in their tracks.  It's just like huntsman said, and the little .243 mushroomed perfectly and stopped, in most cases, just before it broke the skin on the other side and expended every ounce of energy in the target.   The farthest shot on deer stepped off to 90 paces, or probably 75 yards, and bullet placement has always been just where I wanted it.  

I lived just off Natchez Trace Parkway, and have counted over 70 deer in my front yard at one time.  I quit hunting deer for a long time as all I had to do was open the door lay the sand bad down, pick the one I wanted, and get the skinning knife out.

I guess, after all my ranting, what I'm trying to tell you is hit the deer in the right place and it doesn't matter much what cal. or bullet your using, but again, the key is hitting the spot.

Shoot the bullet that shoots best for you in your rifle, and if hit right, you'll get results.....

[Lloyd Smale]

ive shot a fair no. of deer with a 3030 up here its still a very popular round. My father still hunts with one. When he first found 150 grain ammo he thought hed really found something. But hes gone back to 170s Im a firm believer in heavier bullets and penetration. Especially in milder calibers like the 3030. Unlike some ive seen many deer that were decked by 3030s the bullets that are loaded in them are thin skinned bullets that are actually designed just for the 3030 and expand easily at the velocity it produces. I am a gun crank as most of you know but i still laugh at the supposidly in the know gun people that say the 3030 is underpowered for deer. Id like to have a buck for every deer and black bear my old man has taken with his! and if you threw in the ones that i and others at camp have taken with it i could probably retire.

[leverfan]

OKay i have a question. I was told that a bullets energy in foot lbs is how much knock down power a bullet has. But in alot of calibers their is always a smaller caliber with a higher foot per lbs than the larger grain. For example if you are shooting a 150 grain 30-30 powerpoint vs a 170 grain powerpoint which would be more potent? (150:vel-2390,ener-1902.....170: vel-2200 ener-1827 at muzzle. So would that conclude that the 150 is more potent??? So when would u want to use a 170 over 150 if ever??

In order of importance, this is where kinetic energy ends up being ranked in my book:

1.  bullet placement
2.  bullet construction
3.  bullet diameter
4.  bullet weight
5.  velocity (must be sufficient for bullet to work as desired)

Kinetic energy doesn't make the list, because it's irrelevant to how bullets work on game.  Making a hole in a vital organ is the one constant, predictable way to harvest game, which is why low-energy arrows with sharp broadheads can work so well, provided they're well-placed.  

With that in mind, I'll take 170 grain bullets over 150 grain bullets in the 30-30 every time, because they penetrate deeper, assuming similar bullet construction.  If I foul up #1 on my list with my first shot, and I have to shoot at a fleeing, wounded deer, 170 grain bullets are much more likely to reach the chest cavity of the deer.  It's also not uncommon for folks around here to use a 30-30 on large black bear and Roosevelt elk, and the 170 grain bullet will serve better on larger game.

[Buffalogun]

huntsman,

"Stopping power" or "knockdown power" are terms generally used to describe a desired effect of a bullet penetrating a target and then expending maximum energy inside the target, thus causing the target to absorb the full energy of the projectile. Ideally, the bullet would penetrate the target, mushroom to as close to pancake proportions as possible, and stop underneath the skin on the opposite side of a living target.

I took three Whitetails with my .45-70 and cast bullets. Velocity was in the 1,450 fps. range. All three fell at the shot, not taking even one step. Penetration was complete in each case. Never found even one bullet.

No "knockdown or Stopping Power"?


Buffalogun

[fffffg]

you asked the difference in different weights of bullets.. the example i wil give is the 180 speer .358 and the 250 grain .358 speer spitzer.. right in the book it says the 250 grain is t.o heavy of contruction for the .35 remington cartrige..(mayhbe thicker jacket)  the 250 was made for  bigger faster guns,, so i use the 180 grain speer and have not shot a deer with it but it will go thrue a 8 inch tree at 100 yards without any  trouble..  so you need to find out what  bullet is designed for the cartige you want to shoot to have maximum results.. and the bullet velocity/ weitht and construcition  should be proper for the game your after..in the same gun this may mean that different bullets would be used for different game. it goes further than that..  the cannalure or indentation around the bullet is desinged to fit the crimp on the 180 grain  for descent accuracy.. if the crimp is onot in the cannalure the bullet will slide into the case  when it is in the tube and other rounds are being fired..  so alot goes into bullet design. factory bullets for most levers work verry well in them  all things conisdered..  reloading for them is a learning experience..  dave..

[huntsman]

Buffalogun,

Where did you get the idea that I indicated that your cartridge and load did not have knockdown power? I said that IDEALLY a bullet would expend all of its energy in the target to achieve maximum knockdown effect. That doesn't mean that a given cartridge or bullet might not have plenty of extra energy, that is, enough to exit and still expend more than enough energy in the target to knock it down. In the case of the 45-70, that is indeed true. Even half of the energy at normal ranges in this caliber is more than enough to knock down a whitetail deer. The discussion was about the 30-30 caliber, which does need to expend most of its energy in the target to achieve a knockdown on deer-sized game. Let's make sure we are comparing apples to apples here.

There are a lot of cartridges out there that can exit the target and still spend plenty of energy inside the target to achieve knockdown. There are some that are marginal in this regard. The 30-30 falls into the latter category. The 45-70 definitely falls into the first category. In other words, if you are looking for knockdown power in a lower-energy cartridge, you need to pay much closer attention to bullet construction, weight, and velocity. The same is generally true of higher-energy cartridges with high velocity and small bullet weight and diameter. Larger diameter bullets have the most room for error because rapid expansion is not as critical to achieve energy transformation from bullet to target. Especially at lower velocities, a .45 caliber bullet will achieve much better energy transformation to target than a .308 bullet, all else being equal.

[clodbuster]

I heard this argument put forward conceerning this subject and it seemed very logical.   Animals die from the wound caused by the bullet passing through them.  The bigger the wound the more deadly.  The bigger the bullet and the faster it travels through the animal's body, the bigger the wound.  This would seem to call for a well expanded bullet passing completely through the body at high speed,  completely blowing the concept of the bullet stopping under the off-side skin being a good indicator of deadliness.  Exit wounds being better bleeders than entrance wounds is well known also.  What about it?

[Buffalogun]

Huntsman,

I'm not throwing stones, but the paragraph that I quoted sounded very generalized and this question can't be answered with a general answer.

A hit in the forward spine or brain area with enough bullet and velocity will certainly take an animal down on the spot. Knockdown? I don't think so! Bob Hagel has written about a mule deer that he took and during the cleaning he found a bullet lodged against one of the neck vertabrae. Not his bullet, but the bullet of another hunter of days past. Not enough bullet or velocity. Why he recommends against head and neck shots.

It is the bullet strikes in the heart-lung area that we have come to think of as creating "knockdown power".

I have taken whitetails with a number of cartridges over the span of about 30 years. I always go for the heart-lung area. The 30-30 didn't "knockem down". The .35 Remington didn't either. The 6.5x55 didn't, nor did the .270 Win. Neither the 7mm Rem Mag nor the 7mm-08 Rem did the deed. In each case the bullets from the above cartridges penetrated completely.

Only two cartridges have accomplished this feat for me. The .45-70 and the .243 Win. The .50 cal. muzzleloader has also done this. The bullets from the .45-70 and the .243 penetrated completely. Some of the .50 cal. bullets didn't.

Certainly, the .270 Win and the 7mm Rem Mag create more energy than the .243 Win., but they didn't "knockem down". So, it can't be an "energy thing" alone. After all, FMJ bullets can carry the same energy down range as their soft-nosed counterparts. A shot in the heart-lung area with a FMJ won't "knockem down", either. Other folks have also experienced the same performance from the .243 Win. But, there is nothing magical about "knockdown power"

In P.O. Ackley's books it is referred to as the result of "hydraulic shock". If a bullet of a certain construction creates enough "hydraulic shock" when it enters the heart-lung area, it literally shuts down all motor functions. Laboratories sometimes use "ultra-sounds" to mix or break down a product. These ultra-sounds send sonic waves through water and the product. Similar to the "hydraulic shock" created by some high speed bullets.
Obviously, it is velocity coupled with the right kind of bullet construction that produces most of the instantaneous kills that are referred to as "knockdown".

Mr. Ackley created a little hummer called the .17 Ackley Bee. It fired 20g and 25g bullets into the 4,000-3,800 fps. range. It was reported as instant death on mule deer, sheep, coyotes and smaller critters. Under 200 yds. the little bullets exploded inside the vital areas, producing quick kills. This has also been seen by folks usng high speed .224's.

I have found that "knockdown power" can be produced by bullets that penetrate completely, penetrate-but stay inside and by bullets that explode within the carcass!

And clodbuster, I agree. I would much rather have a good blood trail!


Just rambling,

Buffalogun