Terminal Energy Required to Kill Game

[cronhelm]

Anyone have any thoughts on the amount of terminal energy required to cleanly kill game?

I looked in a hunter-ed book and it lists the following as suggested minimums.

Deer, Antelope, Sheep 900 ft/lb
Elk, Small Bear 1500 ft/lb
Moose, Large Bear 2100 ft/lb

My ballistic computer shows that a 300gr MK out of a .338 Mag will have 744 ft/lb at 1900 yds. Does anyone really think that a 300gr bullet travelling at 1050 fps wouldn't cleanly kill a White Tail or a Mule Deer with the proper point of impact?

(Note: I am at 4000 ft altitude so the speed of sound is approx 1050 fps)

This may be a touchy subject but as a newby to long-range hunting I have to ask these questions BEFORE I end up wounding an animal in the field.

Peter Cronhelm

[Darryl Cassel]

Hello Peter

If your just talking about a standard case such as the 338 win. Mag. it would be hard to start out a 300 Gr bullet with enough velocity and retained energy to do what we do with a large wildcat such as the 338/378 Weatherby IMP or the 338/416 Rigby IMP.

If you run the ballistics on your computer, start the 338---300 gr out at 3250 and then run it 3310 (Which I have done with mine) and you will see a full 180 degree turn in ballistic numbers.

When you have a case the size of the 416 Imp and shoot 122 Grs of powder down a 37" barrel it's a whole new ball game.

You can't compare a 338 Win mag to what we shoot.

My Oehler Balistics program shows that there are 3104 FP left at 1000 yards and 1197 FP at 2000 yds which is plenty of energy especially since I ran it at 3250 and not the 3310 that I can run the bullet.

I'm not sure if you were just refering to any 338 or just the 338 Win mag.

Anyway, for the 338 Win mag. the 300 gr bullet may not be the one to use.
In our big boys, it is.

Peter, just read your other post and you did mention the 338 Win Mag. Factory rifle. If it has the 10 twist it will stabilize the 300 gr bullet. The 338 Win mag is a good cartridge for shorter ranges and has killed many deer, elk and Bear.
My 338/416 IMP has a 10 twist and does fine.
keep your ranges shorter and you will do fine with the 338 even with a 250 or 300 gr bullet.

Later
Darryl Cassel

[ 07-19-2001: Message edited by: Darryl Cassel ]

[cronhelm]

Darryl,

I realize that the standard .338 Mag is no match for your big wildcats at very long range. However it is all that I have access to so I am going to have to make do.

I would like to be able to cleanly kill game out to about 1500 to 1600 yds.

As far as the numbers go, I punched the data into my ballistics computer, right out of the loading manual, and what it gave me was:

1900yds Vely 1050fps(transonic) Energy 744 ft/lbs

Keep in mind I am at 4000 ft altitude so the air is a lot thinner up here and we can get a lot more range out of standard cartridges than can be done at sea-level. I am shooting my .243 at 1500 - 1700 yds regularily and expect to break 2000yds soon.

Anyways, my question really was do you think that 744 ft/lbs from a 300gr .338 bullet is enough to kill a deer or anything else for that matter. Keeping in mind that the Hunter-Ed book suggests 900 ft/lbs as a minimum?

From what I have read in your's and others' posts, even a slow moving bullet can cause a huge wound if it tumbles which these big MK bullets tend to do. Therefore retained energy is less important than shot placement and a big bullet.

Peter Cronhelm

[Darryl Cassel]

Peter

The FP is enough to kill. The reason I say this is, My friends and I used to use handguns to hunt deer with. They were 357 mags, 41 Mags and 44 mags. Shots were made at anywhere from 50 yds to a tad over 100 Yds. Just check the ballistics and energy of the normal loads in an 8" pistol using the above mentioned calibers.
You will be surprised how low they are.

We killed a lot of deer with those handguns. One of my friends killed 11 buck in 11 years with his 357 Mag. If I remember correctly, his longest kill was 80 Yards.

If you compare FP of energy at close range to FPs of energy at longer range and they are close to the same, you can make a very good comparison to killing power.
The yardage in between don't mean a heck of a lot. It just so happens that, your 338 mag with 750 FPs of energy at the yards you ran ballistics on, has a lot more energy then the 357 Mag pistol does at the muzzle.

One question, was wondering what kind of a rangefinder do you fellows use there in Alberta?
We hunt at 7500 to 8000 ft in Colorado and I have seen how flat the trajectory is. Have never tried a straight 243 at 2000 yards YET. I have shot mine out to 1450 in PA.

Good Luck
Darryl Cassel

[Dave King]

Peter

I see you posted at 10:43 AM in the "How Far Out Will This Rifle Perform" thread. That post pretty much answers this question as I read it.

I'm not sure where these "standards" remaining energy values come from but I don't generally worry about them too much. Shot placement is far more important than energy (dangerous game not included).

[cronhelm]

Darryl,

You make an excellent point about the handgun energies that can obviously kill cleanly. I will look up some of those energies and see how they compare.

It is interesting that you ask about range-finding. Dave King and I have been working on a "revolutionary" new system of GPS ranging combined with a ballistics computer for a completely integrated ranging system. I have to write the instructions today and then we will be making it available exclusively to the members of this message board to test.

My .243 is not exactly a "straight .243". I have a fast twist, match barrel that allows me to launch moly coated, Berger 95gr VLD's at just under 3300fps. At my altitude this bullet will stay supersonic to approximately 1850 - 1900yds depending on other factors.

I have made a hit at 1890yds already and that was with the scope not being properly setup. I had to aim "by guess and by god" to get onto the target. I have since had the scope mount fixed and should be able to go all the way to 2000yds once I find a place to set up a target and find a windless day.

I am using the lids from 55gal oil drums (24" metal circles) as targets. To see a short story and pictures of my first attempt go to:
http://www.nucleus.com/~cronhelm/index.html

and click on the "Shooting at a Mile" link.

The .243 is a good tool to practice ultra-long-range shooting but it will never carry enough downrange energy to kill anything bigger than a coyote. I did a rough estimation that at 1900yds, the 95gr VLD has approximately the energy of a .380 handgun which is not exactly a lot.

Peter Cronhelm

[Roadrunner]

Peter,

Remember that you can only really accurately shoot a rifle bullet out until it drops below the speed of sound. As it's dropping through the sound barrier, it becomes somewhat unstable and therefore less predictable. Groups shot when the bullet goes sub-sonic have a much larger MOA then groups shot while the bullet is still supersonic. There are many different factors that affect when a particular bullet load will go sub-sonic: altitude, air temp, ammunition temp, humidity ect. So the exact range at which this would happen on any given day is challenging to predict. But as far as any humane hunting goes, at extreme ranges you always want to ensure that your bullet stays super-sonic.

Whenever you hear about the military shooting a fifty cal at say 3000 yrds, it's that they're probably shooting at vehicles and MOA accuracy doesn't matter as much with such large targets; esp when you're shooting many rounds (such as from a machine .

Just my .02

RR