.300 Win/Wea Mag vs 45/70 Govt

[Hueco]

Well, from looking at ballistics, these are three very differnt calibers. That is obvious from the simple measurement, but ballistics are differing as well. Now I have heard it said that the 45/70 can stop anything that moves on earth. No doubt that is true. But my goodness, look at the .300 magnums numbers! About 1300 ft/lbs of energy at muzzle for the 45/70, but an average of 3300 ft/lbs for the Win. mag! The Weatherby magnum is even more powerful than that. It has upwards of 4000 ft/lbs. The largest difference I see is the bullet weight and energy. So what is the big hoopla about the 45/70 being such a super-powerful gun when there exist such calibers as the .300 magnums? Also, how does noise and recoil of the 45/70 relate to the .300 Win./Wea. magnum? Aren't ballistics fascinating?


Hueco

[B Shipley]

A Mack truck doing 70 will do a lot more damage than a Porsche doing 150 when it hits something. The big heavy's will put a very large hole very deep into large dangerous animals. The smaller, faster bullets will put a small hole quite deep as well, but would run out of steam sooner due to the weight and, thus, momentum difference. Look at a ballistics table that compares a .45ACP with a .357. The .45 doesn't have the same energy as the .357, but you'll notice that it seems to lose very little performance as the distance increases. This is all anecdotal, of course.

I await someone with the patience and desire to delineate this with all the equations I promptly forgot from calulus and physics.

[Randy Garrett]

Hueco,

Your observations regarding the 300 Magnums and the 45-70 are a classic example of what is wrong with kinetic energy generation as a measure of effectiveness. The kinetic energy equation squares velocity but does not square bullet weight, thereby "prejudicing" the results towards those calibers that drive relatively light bullets to relatively high velocities. However, when one calculates power by giving equal value to velocity and bullet weight, as in the momentum measurement, the results are totally different. For the sake of this discussion, lets use modern 45-70 ballistics. As reflected by one of our loadings, the 45-70 can drive a 415-grainer to 1850-fps (from a Marlin lever-gun), producing 3150 ft/lbs of kinetic energy and 110 lbs of momentum. The 300 Winchester Magnum drives a 180-grainer to about 3085-fps for 3800 ft/lbs of kinetic energy and 79 lbs of momentum. It now starts to become clear that the manner of measurement tends to determine the outcome. Also, with the various 30 caliber guns it is essential to use expanding bullets in order to effect a clean and quick kill, whereas with the 45-70 bullet diameter is so substantial that expansion is not required to kill cleanly. When one goes to non-expanding bullets, the penetration depth achieved is much greater than can be achieved with any expanding bullet from any caliber. Indeed, about the most penetration that can be achieved in wet newspapers (a common test medium) with premium expanding bullets in any caliber is about 18-inches. With the 45-70 and proper hard-cast bullets, penetration depth can range anywhere from 36-inches with the lighter castings to 70-inches with the heaviest.

High velocity guns shine where long-range shooting is required. However, when the game is extremely tough the various 300 Magnums leave much to be desired, tending to over-expand and invariably producing shallow penetration channels.

A properly loaded 45-70 will shoot lengthwise through anything in North America, something the various high velocity calibers simply cannot do or even come close to.

Best regards, Randy Garrett www.garrettcartridges.com (http://www.garrettcartridges.com)

[This message has been edited by Randy Garrett (edited January 05, 2000).]

[ak9]

Do not get deflected by the factory loads. Most are light loaded for liabiltiy on the off chance some one might put a new load in an old rifle. In a modern rifle such as the marlin guide gun, substantially higher pressures can be handled producing much improved muzzle velocities which make them very effective for any game in North Ameica and most of Africa. Check out Col. Coopers writings on the 45/70 and it effectiveness against the largest African game. The copilot rifle is prominently featured.www.wildwest.com. There are actually three different power chamberings for the 45/79. Checkout the Bufalo Bore pages listings for this round.

[Bob Locke]

I want to second Randy's opinion of measuring "effectiveness". To me, momentum has always been more important than energy. Momentum is the true measure of knockdown capability, not muzzle energy (hence, the Mack truck vs. Porsche analogy). That is why .45 ACP's run circles around 9mm's from a stopping perspective, though they measure about the same energy at the muzzle due to the 9mm's significantly higher veolcity.

That being said, take with you the rifle that suits the game and hunting conditions that you are likely to face. For North America, the .300 Win mag (or the Weatherby) would certainly get the job done. So would the .30-06, for that matter. For large game in Africa, I would MUCH rather have a .45-70.

[Hueco]

Ok, I now have a grasp on this. I had previously read an article "The Mystique of Killing Power" and found it very interesting. Until now I didn't realize just how much that the actual effectiveness can "differ" from the numbers. Thank you for your patience in explaining that to me. I do really appreciate it.


Hueco

[Art Eatman]

Just to add a bit, consider that deer and elk rarely exceed 18" from side to side, so a lot of the .30s will go on through. Their expansion creates a large wound channel, and the typical fairly-large exit wound allows a good blood trail if you need to track. And, most of our black bear aren't all that big.

Now consider bison or African buffalo. A .30 might kill one, but you may well track for a helluva long distance before you find him; and in the case of the African critter, he may well find you. For dangerous game, you would want a load which both penetrates and makes a large wound channel, with almost zero potential for "blowing up" upon entry or hitting, say, a foreleg bone. There's no magic, of course; a gut shot with a .460 Weatherby is a bum deal for you if that "prey" decides to get even...

There are always "circumstances", of course. One's skill, one's experience, one's nerve. For instance, Karamojo Bell killed hundreds of elephants with a 6.5 Mannlicher. BUT, he had learned (the hard way, I presume) exactly where the bullet needed to hit, and at what angle. And his typical shooting range was measured in feet, not yards. In his day, elephants had not yet learned to fear men with guns...

I guess the key, in today's world, is the hunter's ethic that you use a suitable gun for the game you're after, to get a quick, clean kill.

Regards, Art

[Glamdring]

So how would a 300 Win loaded with 220 Woodleigh FMJ @ ~2600 fps compare to the 45-70 loaded with hard cast 415/500/530 grain bullet for penetration?

The SD for a 220 grain 308" and 500 grain .458" are equal.

[Al Thompson]

SD is the hidden number..

Glamdring, assuming like construction and speed, they should be the same for penetration.

Giz

[Glamdring]

Yeah but a 500 grain bullet from a 45-70 won't hit 1600 fps So the 300 should have at least a 1000 fps advantage.

Just wondering what actual penetration differences would be in test medium.

I know at least one PH had some clients take Buff with a 300 Win and 220 solids, though he was backing them up with a heavy.

And I can't help but think if Bell was able to take Jumbo with 7mm 173 grain FMJ @ 2300-2400 fps that a 308" 220 grain @ 2600 fps would work.

BTW 500 grain 458 isn't exactly the same SD as 220 grain 308" but it does equal the 400 grain bullet from a 416 Rem/Rigby or the 470 NE with 500 grain bullet.

7mm 175 grain sd= .310
.308" 220 grain sd= .331
.375" 300 grain sd= .305
.416" 400 grain sd= .330
.458" 500 grain sd= .341
.470" 500 grain sd= .329