Does Sectional Density and the other Formulas work on Elk? (2024)

Does Sectional Density and the other Formulas work on Elk?

#57905209/14/05

Central Idaho

Do you base your rifle choice or cartridge choice for Elk on/ The bullet/SD/energy/caliber/tradjectory/tko/muzzle velocity/lethality factor/recoil/ or "Shot Placement" with any caliber or bullet?

Jayco

Re: Does Sectional Density and the other Formulas work on Elk?

#57905309/14/05

south central Kansas

Re: Does Sectional Density and the other Formulas work on Elk?

#57905409/14/05

wyoming

Re: Does Sectional Density and the other Formulas work on Elk?

#57905509/14/05

6491 Feet Above Sea Level

Given a reasonably suitable cartridge and bullet, shot placement is king in my book. That said, I do have strong preferences.

First, the bullet. I prefer a bullet that expands but does so in a controlled fashion, to about 2x caliber or up to about .65�, and retains most of its weight. That means I don�t want any part of a bullet that �pencils through� or one that pancakes on impact or one that acts like a varmint bullet and blows up. I also want a bullet with a minimum weight of about 150g for elk. Although the 160g North Fork bonded bullets are what I stoke my 7mm Mag with now, the 160g Speer Grand Slams have been solid performers at ranges close and far for over 20 years. Last Sunday I finished working up my .300 Win Mag load for elk, a 180g North Fork. Haven�t had a chance to take an elk with either combination but was very impressed with the performance of my .45-70 and a 350g North Fork on a 6x6 bull a couple years ago. For high-velocity (3000fps and over) bolt guns I think the Speer Trophy Bonded and North Fork are as good as it gets, with the Swift A-Frame a close second. All offer positively controlled expansion with a bonded-core. Nosler Partitions also offer positively controlled expansion but tend to lose their unbonded front core, and I would rate them in third place with bonded core bullets like the Accubond, Interbond, and Scirocco. Standard cup-and-core bullets, IMHO, are best left at home when velocities are over 3000fps. Standard cup-and-core bullets like the Speer 170g should work just fine in the relatively sedate .30-30, but a more solidly constructed bullet like the 170g Nosler Partition might fare better if heavy bone is encountered.

A bullet�s original Sectional Density, by itself, means little. A bullet that fails to expand will often get great penetration but cause minimal damage. By contrast, a bullet that pancakes ends up with the sectional density of a flyswatter. That said, I�ve often stated that I feel a .270 Win with a bullet weight of 150g (SD .279) is the minimum I recommend for elk. In the 7mm�s I like the 160g weight (SD .283) and in the .308�s I like a 170g for the .30-30 (SD .256) and a 180g in bolt guns (SD .271). Reaching up into the .338�s and larger I am quite willing to accept bullets with lower SD�s simply because they have more weight and larger diameters. For example, the 350g bullet in a .45-70 has a SD of .238 but is a very effective choice.

Energy is an interesting tool by which to compare different loads but is a crude tool at best and, IMHO, places too much emphasis on velocity. Still, if you use a bullet matched to its velocity, 1000 foot pounds of energy will generally do the job efficiently given good placement. My 7mm Mag and .300 Win Mag will deliver 1000 fpe out past 400 yards, which is further than I would take a shot.

Trajectory is somewhat important but is secondary to accuracy. I would rather shoot my .45-70 at 300 yards, knowing it will group about 4-5� and that the bullet drop is 22�, than a .300 RUM that groups 9� at that range. When choosing my latest acquisition, a .300 Win Mag, I did so with the knowledge that it would shoot �flat enough� at any range I would use it and that the flatter shooting .300 Weatherby or RUM cartridges would not provide me with any meaningful advantage. My hunting buddy Dave and I were out at the range last Sunday, shooting steel gongs with the .30-30 and .375Win at 200 and 300 yards - no problem, just need to know where to aim. (Our loads in these cartridges have are pretty much dead on at 200.) Then we backed up to 400 yards and used the .257 Roberts and .300 Win Mag.

Muzzle velocity by itself means little � I wouldn�t consider hunting elk with my 4000fps 22-250 loads, but I have hunted them with my .44 Mag carbine and 240g JSP loads that run 1881fps at the muzzle. And, as you know, my last elk was a 6x6 bull at 213 lasered yards with a 2181fps 350g North Fork from my .45-70. For years I used 160g Grand Slams in my 7mm Mag at 2850fps and my new 160g North Fork loads run a few fps faster and are more accurate. The 180g North Fork loads I finished developing for the .300 Win Mag last weekend run 3032fps.

When I choose my first elk rifle back in 1981, recoil � or rather a fear of it � was a big factor. My mentor suggested a 7mm Mag would be more than adequate but without the recoil of a .300 or .338. He was correct, but over the years I have come to believe that a heavier .308� bullet is a better choice. Since I got my .45-70 and developed loads from 7 foot-pounds to 48 foot-pounds recoil, I view recoil in a whole new light. For elk guns it just doesn�t matter much, provided the shooter can use the rifle well. For benchrest, varmint and plinking rifles, excessive recoil can spoil the fun in a hurry.

TKO and �lethality factor� have never been a consideration prior to choosing a rifle, although I admit to calculating TKO for various loads after I developed them. Couldn�t tell you what the results were, though as my interest was purely transient and I didn�t record the values.

After all that we�re back to where I started � choose a reasonably good bullet with a construction matched to its velocity and place it well. Then break out the skinning knives...

Re: Does Sectional Density and the other Formulas work on Elk?

#57905609/15/05

Michigan

When it comes to elk hunting, or any big game hunting for that matter my rank in order of importance is:
1. Hunting ability and mental attitude
2. Shot placement
3. Bullet Construction
4. Being in shape
5. Boots
6. Optics
7. Clothing.
.
.
.
.
...Caliber.

As much fun as it is to banter and nitpick about calibers, cartridges, bullets and such I tend to believe that at the end of the day those factors rank pretty low on the list of importance for elk hunting. A well placed, well constructed bullet from any "adequate" cartridge equals a dead animal. Putting yourself in position to make that shot is the tough part.

Jeff

Re: Does Sectional Density and the other Formulas work on Elk?

#57905709/15/05

Central Idaho

It seems to me that some intelligent people with lots of hunting experience came up with ways(Atleast to them) to measure the effects of bullets etc on game by these mathmatical formula's such as:
TKO
Designed by John �Pondoro� Taylor of Zimbabwe, Africa. John was an African Professional Hunter who killed thousands of game animals during his years of hunting. He also wrote several books on Africa hunting and of the guns used for Africa�s unique game. Through his years of experience and experimentation he generated the formula that bears his name. Take the bullet weight in lbs., weight in grains divided by 7000, times velocity in ft. sec., times caliber in thousandths of an inch. Thus produces an index value that can be related to reflect killing power, or TKO.

Kinetic energy is the energy of motion. An object which has motion - whether it be vertical or horizontal motion - has kinetic energy.

A ballistic coefficient (BC) is the ratio of the sectional density of a bullet to it's coefficient of form (I). A BC is in fact a numerical representation of the ability of a bullet to fly. An average hunting bullet produced by one of our competitors has a ballistic coefficient upwards of 0.4 to 0.5. At Lost River Ballistic Technologies, Inc. we are able to produce hunting bullets with ballistic coefficients upwards of 0.7, which results in a more precise and accurate bullet. Our J40 .308-220 grain target bullet has a ballistic coefficient of 0.930. By increasing the ability of a bullet to fly, you, as our customer, will see the results.
Sectional density (SD) is a bullet's weight, in pounds, divided by the square of it's diameter, in inches. SD is a numerical representation of a bullet's ability to carry it's momentum forward. The higher the SD, the higher the weight per cross-sectional area. Shape makes no difference in the sectional density. For example, all 30 caliber (.308) bullets that weigh 180 grains have the same sectional density, .270, regardless of their shape.

Lethality Index

John Wooters is another old salt who ought to be listened to reverently. I love Wooters, even if he is a bit of a curmudgeon (when one has graduated to the plateau of veneration upon which he resides, one can be forgiven for curmudgeonhood). No doubt frustrated with the ceaseless litany of kinetic energy figures, he concocted a formula for what he felt was a better measure of a bullet's effectiveness on game. Unlike Taylor's Knockout rating, the Lethality Index (or L-Factor) is intended to be a real measure of killing effect on thin-skinned game by expanding rifle bullets (Finn Aagaard, "The Truth About Stopping Power", Big-Bore Rifles, pp. 8 - 11). The author's formula is described below:

LI = Kinetic Energy (ft-lbs) x Sectional Density x Bullet Diameter (in)

Now I am not sure the Elk are any better at math than I am,so I expect that these calculations do not hold true for all game and bullets but there is some merit in all of them.

I certainly don't pay attention to any of it and I doubt the Elk do either, other than "Bullet Choice" and "Shot Placement".
Interesting though!!!

Jayco

Re: Does Sectional Density and the other Formulas work on Elk?

#57905809/15/05

How do your bullets (Lost River) expand on game at close and long range?

They look like Barnes X bullets, but without the hollow-point.

Intuitively, they look like they would act like a solid and not offer any diameter to the wound channel, though their B.C.s are impressive (if accurate).

I spoke with one of the Lost River reps at the SHOT show last year in Vegas and he (young guy) hadn't even tried them out on game himself yet and he said that he had no samples to give me to test their expansion in test media.

Would you have some before and after photos of your bullets in animal glue, ballistic gelatin or game to share with us? The Dall sheep on the website is an old photo and there are no bullet 'after' photos available.

Thanks for your time. We appreciate results.

Re: Does Sectional Density and the other Formulas work on Elk?

#57905909/15/05

logcutter, have you used the Lost River bullets and how do they expand on game at close and long range?

They look like Barnes X bullets, but without the hollow-point.

Intuitively, they look like they would act like a solid and not offer any diameter to the wound channel, though their B.C.s are impressive (if accurate).

I spoke with one of the Lost River reps at the SHOT show last year in Vegas and he (young guy) hadn't even tried them out on game himself yet and he said that he had no samples to give me to test their expansion in test media.

Would you or anyone have some before and after photos of them in animal glue, ballistic gelatin or game to share with us? The Dall sheep on the website is an old photo and there are no bullet 'after' photos available.

Thanks

Re: Does Sectional Density and the other Formulas work on Elk?

#57906009/15/05

logcutter, have you used the Lost River bullets and how do they expand on game at close and long range?

They look like Barnes X bullets, but without the hollow-point.

Intuitively, they look like they would act like a solid and not offer any diameter to the wound channel, though their B.C.s are impressive (if accurate).

I spoke with one of the Lost River reps at the SHOT show last year in Vegas and he (young guy) hadn't even tried them out on game himself yet and he said that he had no samples to give me to test their expansion in test media.

Would you or anyone have some before and after photos of them in animal glue, ballistic gelatin or game to share with us? The Dall sheep on the website is an old photo and there are no bullet 'after' photos available.

Thanks

Re: Does Sectional Density and the other Formulas work on Elk?

#57906109/15/05

Central Idaho

Canadianlefty-Thats the first I have ever heard of them so you made me look.

Very interesting but I have not tried them.I kinda come from the old school of thought..If it ain't broke don't fix it!!!No secret that I am a Nosler fan from the .270 to my .300 Win Mag but I did try the Trophy Bonded 140 grain in the .270 and it performed every bit as good as the Nosler if not better.

Bullets like the North Fork and maybe this one you talk about are great bullets,but I just stick to what has worked for me year after year if I get lucky enough to get one.

It will be interesting to see if anyone has tried these as I love to here new bullet story's on game.

Jayco

Re: Does Sectional Density and the other Formulas work on Elk?

#57906209/15/05

I got the impressionm from your prior post that you may have tried them out. re:

"A ballistic coefficient (BC) is the ratio of the sectional density of a bullet to it's coefficient of form (I). A BC is in fact a numerical representation of the ability of a bullet to fly. An average hunting bullet produced by one of our competitors has a ballistic coefficient upwards of 0.4 to 0.5. At Lost River Ballistic Technologies, Inc. we are able to produce hunting bullets with ballistic coefficients upwards of 0.7, which results in a more precise and accurate bullet. Our J40 .308-220 grain target bullet has a ballistic coefficient of 0.930. By increasing the ability of a bullet to fly, you, as our customer, will see the results. "

Yes, I did see that bullet on their site- it does seem interesting, BUT I fear that they do not expand properly.

Thanks for looking.

Re: Does Sectional Density and the other Formulas work on Elk?

#57906309/15/05

New Jersey

Logcutter

You forgot one main principal in John Taylor's knock out formula, it was designed to rate solids not soft point bullets. I have said this many times and i believe it with all my heart, energy, S.D. lethality formulas yadda yadda yadda do not kill big game, destroying the lungs, and or heart, or central nervous system is what puts an animal down.

What seems very prevalent with today's hunters is they want to extend their range, which is O.K. up to a point. But when does hunting become shooting? At how many hundreds of yards is it just a target and not game? I guess that each man has to answer these questions to himself, but i strongly believe that if every rifle hunter also bowhunted things would be quite different in rifle and cartridge selection.

Another thing that i have noticed is most hunters fully expect their shot to level game, and when they run off, the hunter seems to be shocked. Most big game will run and its very unrealistic to expect bang/flops every time. I actually enjoy tracking animals and have learned a lot about their escape trails and other important factors. If you use a controlled expansion bullet, and put it where it counts, tracking is easy. If i shoot an animal, and it doesnt go down, im right on em, and have hit them on the run, just for insurance. Even if they do go right down, im still on em with my scope and a fresh round in the chamber, expecting them to jump up and run at any second.

Re: Does Sectional Density and the other Formulas work on Elk?

#57906409/15/05

Westbrook, Maine USA

Re: Does Sectional Density and the other Formulas work on Elk?

#57906509/16/05

Tigard OR

Re: Does Sectional Density and the other Formulas work on Elk?

#57906609/18/05

Alberta Canada

I have to agree.Bullet placement,velocity and bullet construction determine the damage done to the animal,which is what determines if there will be a clean kill or a wounded animal.

Re: Does Sectional Density and the other Formulas work on Elk?

#57906709/18/05

precise shot placement , using a reasonable caliber for the game hunted, and understanding the games anatomy 70%

Quality bullet construction, designed for deep
penetration with controlled expansion and using that bullet within the velocity range its designed for 20%

factors you can,t control 10%

but Id suggest lots of practice with your sellected equipment, sellecting a bullet having a minimum of a .260 sectional density,and getting in as close as you can before firing can increase your chance for success,and knowing your personal limits and resisting the urge to fire on low percentage shots helps

Re: Does Sectional Density and the other Formulas work on Elk?

#57906809/20/05

Joplin MO

Re: Does Sectional Density and the other Formulas work on Elk?

#57906909/21/05

Colorado Springs, CO, USA

Re: Does Sectional Density and the other Formulas work on Elk?

#57907009/21/05

lapine oregon

Re: Does Sectional Density and the other Formulas work on Elk?

#57907109/21/05

Tigard OR

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