416 Rigby vs 458 WinMag a civil discussion

[TTundra]

This is great info! I hope others can shed more light! Thank you!!!

Yes he did as most in that era did, the 416 Rigby was almost unheard of and the 458WinMag didn’t exist for much of his hunting career.
But when the 458 came out he fully endorsed it!

Just curious, are you asking about the 458Win or is there a 458 B&M?

There has been a lot of research done on the 416 B&M and 458 B&M. Probably more done on the 416 and 458 in modern projectiles side by side than any if the large manufactures in both test media and in field.

Michael's testing over the years is likely one of the best resources for 416 vs 458 projectiles albeit not 416 Rigby vs 458 Win

 

[Green Chile]

Now the 416 Rigby and the 458 WinMag are very close in energy but the 458 has better SD, better momentum, and a larger meplat…

How is this statement made with no mention of bullet weight or velocity? Are you talking about factory loadings of 400 grains in 416 and 500 grains in 458? There are also many factors of bullet shape/design that contribute to the answer.

 

[CZDiesel]

How is this statement made with no mention of bullet weight or velocity? Are you talking about factory loadings of 400 grains in 416 and 500 grains in 458? There are also many factors of bullet shape/design that contribute to the answer.

You are right, I should have included that, my mistake. I guess I just assumed that everyone would take it as the standard for each, 400gr at 2400ftps for the 416 and 500gr at 2150 for the 458. Apologies for not stating that…
And yes there are many bullet designs and shapes but both are so common that the offerings should be the same for both. Again I assumed that everyone would think shooting the same bullets as in both shooting the Hornady DGS or Custom CEB or whatever…

 

[CZDiesel]

There has been a lot of research done on the 416 B&M and 458 B&M. Probably more done on the 416 and 458 in modern projectiles side by side than any if the large manufactures in both test media and in field.

Michael's testing over the years is likely one of the best resources for 416 vs 458 projectiles albeit not 416 Rigby vs 458 Win

I hope he chimes in!

 

[Sarg]

Interesting to know which has better penetration, the common thought is the .416 400gr out of the main .416s was superior to .458Win with .500gr but I suspect not the .450Rigby or Weatherby ?

I have had old factory Winchester.458Win White box 500gr or 510gr solid go in the Ass & exit out the nose of a wounded fleeing Buffalo, I was a little surprised at that myself & snapped a couple of photos.

Could only be my.458Win as hunter was using .338Rem Ultra Mag !

 

[intj]

Hey!!! My thread on indecision between the 416 Rem and 458 Lott was civil. Just sayin'.........

I think that @Mark A Ouellette nails it. The reason that both theory and experience favor the 416/400 at 2400 fps for penetration is because the smaller frontal area requires less force to penetrate vs the larger calibers. Even though the 458/500 has a higher SD, the SD isn't high enough with a 500 grainer at 2150 fps to overcome the lesser resistance and momentum of the 416/400.

Remember, PO Ackley showed us that a 40 grain bullet from a 220 Swift would punch a hole in armor plating where a 168 grain 30-06 armor piercing round would not.

What I want to know is if a 458/500 at 2300 fps will out penetrate a 416/400 at 2400 fps. With well designed solids, the penetration should increase with velocity, at least to a point. I don't know what that point is. I would think that that given the proper velocity, and 458/500 would out penetrate a 416/400. But I don't know.

I do remember hearing about how the 460 Wby shooting a 500 grainer at 2700 for had poor penetration, but that could have been due to poor bullet design back in the day.

 

[grand veneur]

The SD does not only play a role in the depth of penetration of a bullet. Other parameters are also important, especially the impact velocity. In our case the bullet design and the SD of the bullets can be seen as fairly comparable. For this reason the impact velocity will make the difference and the cartridge 416 Rigby offers more velocity than the cartridge 458 Winchester Magnum.

The cartridge 460 Weatherby Magnum is ahead of the cartridge 416 Rigby when it comes to all of this. Penetration can be, due to a high impact velocity, sometime not as good by using old classic SP bullets, but there is a great shock effect that compensates for a lot.