Home Forums Hunting & Shooting Elk Hunting 257 weatherby or 7mm-08

Well, you didn't tell anything about the rifles themselves... I am imagining that the 7mm-08 is housed in a rifle that is a more pleasant "carry", IE smaller and lighter, so IF that's the case then the 7-08 wins hands down just on that alone.

As far as on the merits of the two calibers, I would again go with 7mm-08. I would load it with either 150 or 160-gn Partitions, or a 140 or 150-gn TSX (if such a thing exists).

7mm-08 is, like just about everything based on the .308 case, a wonderfully efficient cartridge... and while a .25 will certainly kill an elk, or an elephant for that matter, I think the bigger, heavier bullet of the 7-08 is a real advantage with elk.


Now off to read the thread and see if anyone agrees with me! :-)
-jeff

I killed a bunch of blacktail with a 7mm-08 and 150-gn Partitions (the rifle didn't like the 140's). I never lost one, but I did ALMOST lose a very nice buck:



Sorry for the bad scan of a bad photo to begin with...

That was shot solidly through both lungs. That buck, and another good one that I had to track for 100 yards, plus the barrel being shot out on my 7-08 <g>, prompted me to re-barrel that rifle to .358 Win, which at the very least leaves much more blood trail than 7mm-08...

Anyway, not diss-ing the 7mm-08; I still own one in a Mountain Rifle and I love the caliber and would hunt anything up to elk with it. But I guess my point is that, overkill or not, there are reasons to use something bigger on deer than 7mm-08 for some situations. That said, I'm not a fan a going into warp-speed for more power; I want a bigger, fatter bullet at a moderate 2600 fps or so.

-jeff

If we use the gun argument, I can see a 7-08, but the ballistics argument doesnt hold any water.

If you compare the 120g NP factory load in the .257 to the 140g 7-08 factory load (federal ballistics website), the .257 kills the 7-08.

The .257 with a muzzle velocity(MV) of 3305 fps has a muzzle energy(ME) of 2910 ft/lbs. The 7-08 with a MV of 2820 fps has a ME of 2472 ft/lbs. That is almost 500 fps and 450 ft/lbs the 7-08 give up to the .257. Since most game isnt killed at the muzzle, lets compare at 300 yards. At 300 yards the .257 has a listed velocity of 2570 fps and 1760 ft/lbs, whereas the 7-08 has a listed velocity of 2162 fps and 1452 ft/lbs of energy. Still a 400 fps difference and 300 ft/lb difference in favor of the .257.

Lets compare the 120g .257 to 150g 7-08, the 7-08 loses at muzzle by 650 fps and 570 ft/lbs and at 300 yards it loses 500 fps and almost 400 ft/lbs.

With comparably constructed bullets, the .257 wins hands down ballistically.

There is more to bullet effectiveness than just velocity and striking energy...

Such as?

We are comparing apples to apples, NPT to NPT or TSX to TSX. Ballistically, the .257 WM wins.

Momentum, the 120g and 150g bullet's momentum is nearly identical.

Why is bigger/heavier/slower better than smaller/lighter/faster if similarly constructed bullets?

Bullet diameter: wound channel, exit hole diameter.

I never have, and never will, kill an elk with a .25, so hopefully someone who has seen it done, or done it, will chime in.

My OPINION, based on seeing and helping dismember a half-dozen elk and killing one small one, is that with elk bigger is better. Bore sizes between .30 and .35 seem to be about optimal. 7mm and .280 certainly work too.

By your argument, a blazing .22 at 4000 fps would be an elk load.

Elk are big animals, and big holes are a good thing. They don't need to be humongous, but .25 is getting a little small, IMHO. Also, a .25 at 3300 fps is risking bullet problems on big bones, even with a great bullet.

If I was forced to hunt elk with a .25, especially a fast one, I'd restrict my shots to broadside and try to keep the range at least 100 yards or greater.

If I was using an appropriatly-loaded 7mm-08, the angles I would be comfortable taking would be much greater. A 7mm-08 would drive a 160-gn bullet deep into a lot of elk.

That's what I think anyway.

-jeff

Kodiak,
I'll look for it tonight.

Thanks

Jordan, I will play devils advocate. If a good bullet expands to twice its diameter, the .257 will be 0.514 inches, the 0.284 will expand to 0.578. Are you insinuating that 0.054 inches in exit hole will be detectable to the human eye or the elk will be able to tell the difference?

My argument is that the .257 will have a larger wound diameter because of the increased velocity of the bullet and the larger hydrostatic energy.

Jeff, my argument nowhere mentions the .22 at 4000 fps. We are comparing the ballistics of the .257WM to the 7-08. Ask JB if an elk has ever been killed with a .257 caliber bullet.

kyreloader,

I understand you didn't mention .22's.... but let's extend your line of thinking a little and see where it goes. In the process, we will find that you too have a line in the sand, so to speak, with regards to minimum for elk...

You are saying a fast .25 would work. What is wrong with a very fast .22, then, of comparable ft-lbs? Are you saying that a .22 expanded to twice it's diameter, .44, is going to be noticably different to the elk, or to the human eye, than your .25 expanded to .514? We are talking less than 8/100's of an inch difference after all. Trivial!

And yet we all know that a hyper-fast .22 would be a poor choice.

The mechanisms that make a fast .22 less "good" than a .257 Weatherby, make the fast .25 less ideal than a 7mm-08.

-jeff

Exactly Jeff.

kyreloader,
First of all, the term "hydrostatic energy" is an oxymoron. Second of all, I have yet to see a difference in the way a few hundred feet per second determine wound channel diameter or volume.

It's not a difference of 0.054" between the two bullets, it's the difference in volume of the wound channel created by that 0.054" expanding rapidly upon impact.
After all, to our reasoning, would 0.162" really make much of a difference between an expanded .257" bullet and an expanded .338" bullet? But yet we all know that there is a world of difference in effectiveness on game. Both will get the job done, but there is a significant difference in the animals reaction to the bullet striking. Where do we draw the line of what makes a difference and what doesn't? Is there a difference between a .243 and a .257? How about a .243 and a .264? How about a .243 and a .577? You see my point?

I see your point, mine is that ballistically the .257 WM is superior to the 7-08.

Why is my wound cavity with a 100g TSX .25-06 bullet at 3450 fps larger than my father's 150g TSX .270 Win bullet at 2950 fps when tested in the bullet test tube if 500 fps isnt important to wound diameter?

How much volume difference does 0.054" expanding rapidly create?

The differences between the .257 bullet and the .338 bullet has to do with the momentum, velocity and energy of the two bullets. I think a difference of 1000 ft/lbs of energy between the .257 and .338 should make a difference in an animals reaction to bullet striking and overall effectiveness.

Jeff, a .22 does not have comparable foot pounds. A .22-250 with a 60g NP at 3500 fps only has 1632 ft/lbs and momentum figures of 210,000. Balllistically not on the same planet-it is a bad choice because it doesn't have enough energy, momentum.

I see your point but ballistically the .257WM is superior. Real world will it matter? I am arguing that it will not.

I see your point as well, but even if the .338" bullet had equal momentum and energy, I will venture a guess to say that it will be more effective than the .257" bullet.

"How much volume does 0.054" expanding rapidly create?" Enough to make a difference.

A wound cavity in the bullet test tube (read: consistent medium) is different than it would be in an elk for example because the elk is not a hydraulic medium like most test mediums are, but instead are largely pericardium, lung, airspace, bone, and skin/hair. Now I'm not saying that velocity doesn't create a bigger wound channel in an ANIMAL, but just as with the bullet diameter comparison, where do we draw the line? Does 25 fps make a difference? Does 200? What about 2000? I'm trying to say that it's all a compromise. More velocity with the .257 and more surface area in the expanded 7mm bullet. The .257 may have the external ballistic advantage, but I would wager that the 7mm would have the "consistently reliable animal reaction" advantage. Both will make the elk sick enough to fill my freezer though.

What about if we took a .177" bullet and gave it enough velocity to match the .257" in momentum and energy. Would they be equally effective on elk?

That would only be about 20,000 fps with the .177.

I agree, Jordan, both .257 and 7-08 would make them sick enough to fill my freezer.

Since, for a given mass, momentum increases linearly with velocity but kinetic energy increases quadratically I think you're going to run into trouble trying to get two different masses to have the same kinetic energy if you've matched momentum, and vice versa.

Heavier and heavier isn't better in the extreme either. I believe a 16 pound bowling ball at about 3.6 fps has the same momentum as a 150 grain bullet at 2700. Now which is the better elk killer?

Having no elk killing experience I can't tell you which will cartridge will do better, but I think I can illustrate what happens when numbers get mishandled.

mathman

Good illustration mathman. The actual dynamics are far more complicated than a single number (momentum or energy) can possibly accurately represent. The 'bowling ball' and 'hyper speed needle' counterexamples illustrate the fallacy. Bottomline is that a sufficiently 'damaging' wound has to be inflicted, and placement and bullet performance have to enter into it as well as velocity and bullet weight and caliber.

Why not compare the 100 or 120 TSX out of the 257Roy to the 120 TSX at about 3,100 out of the 7-08? I don't have the numbers right in front of me but that would seem a more logical comparison.

Kodiak, the article is in Handloader No. 237, October 2005. PM sent.

That's exactly what I'm trying to say. There is more to the equation than just velocity, momentum, and energy. If too much emphasis is placed on any one of the many variables, it begins to stray from reality. Both the bowling ball and the hyper-velocity needle are unreasonable as neither would be extremely effective on dispatching an elk, but preferably we'd use a bullet somewhere in between the two and have a dead elk in short order.