416 Rigby vs 458 WinMag a civil discussion

CZDiesel

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There is a very recent thread where the OP was pondering between a 416 and a 458 and there were many that posted that the 416 will out penetrate the 458…
Now the OP had said that he posted because he wanted both feedback but also because it’s fun to have these discussions. So I thought I’d follow up along the same lines in that let’s keep it fun and informative!

So it’s interesting to me to hear some here say that the 416 will out penetrate the 458? I’ve never heard that before, doesn’t mean it’s not true though?
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… Theoretically this should all lead to not only more penetration but much more damage along the way?
In real use, not theory, my PH told me without hesitation the 458 WinMag, both Dalton and York of the very know Dalton and York Safaris use the 458 WinMag, Kevin “Doctari” Robertson calls the 458 the “Gold Standard”, and Taylor wrote in his book that while the 416 is a much better all around cartridge it’s not a stopping rifle where the 458 is?
Now in all of this penetration is key! So can anyone show where the 416 which has less energy, less momentum, smaller meplat, and less weight can out penetrate the 458?
Let the fight begin lol
 
Hi CZDiesel,

I have no experience with the 416 Rigby but have had a bit with the .458 Win Mag, having owned 5 and reloaded for all of them...

From what l have read, and from what l have been lead to believe, the problem with the .458 not penetrating sufficiently is when the expected velocity wasn't achieved.
When the desired 2150fps with a 500gn bullet was achieved l have never heard of anyone complaining of it's performance on dangerous game.
In fact, isn't 2150fps with a 500gn bullet the benchmark for DG?

When reloading for the .458 l have never had a problem reaching 2150fps with a 480-500gn projectile.
The highest l have reached with a 500gn projectile is 2220fps and this was from the 24" barrel of my Winchester M70.
I had a custom CZ550 in .458WM with a 21" barrel and l was still able to reach 2150fps with a 500gn Woodleigh. I did this by loading to suit the long magazine of the CZ and using a Lee FCD to crimp the bullet.

I also managed 2100fps with the 550gn Woodleigh and 2300fps with the 450gn Woodleigh Hydro in the .458 Win Mag.
I just can't imagine either of these loads lacking penetration and with modern bullets like the CEB that weigh less - but penetrate more, I could only imagine the .458 Win Mag being more effective than ever...

So l don't know if any of this helps at all but l guess what l'm trying to say is that it's not hard to reach 2150fps with a 500gn bullet out of the .458 Win Mag.
I've done it in all of my .458's I've owned and I'm a nurse - not a PH, so if l can do it anyone can...
And like l said earlier, l've never read of any complaints of the performance of a 500gn bullet at 2150fps on DG...

Russ
 
There is a very recent thread where the OP was pondering between a 416 and a 458 and there were many that posted that the 416 will out penetrate the 458…

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… Theoretically this should all lead to not only more penetration but much more damage along the way?
This could not be any more simple...

Example:
A. With 10 pounds (4.5 kilos) of force pushing a unsharpened pencil (flat surface/meplat .25" (5mm) diameter against their skin, will that penetrate (break the skin)? Probably not.
B. Try the same with a flat meplat shaft of .1" (2.54mm). Does the 10lbs pressure push the smaller diameter shaft through the skin? Maybe with a much better chance than the larger diameter shaft.
C. Decrease the diameter of the shaft to .05". Certainly that will penetrate all but the toughest skin.

If all else is equal such as energy and bullet shape and material, the smaller diameter bullet will encounter LESS resistance to it penetrating.

What I think you are not factoring into the results of dead dangerous game is that with equal energy, the larger diameter bullet will TRANSFER more energy quicker than will the smaller diameter bullet. That is part of Taylor's Knock Out Factor.

https://en.wikipedia.org/wiki/Taylor_knock-out_factor

The Taylor KO factor (TKOF) multiplies bullet mass (measured in grains) by muzzle velocity (measured in feet per second) by bullet diameter (measured in inches) and then divides the product by 7,000, converting the value from grains to pounds and giving a numerical value from 0 to ~150 for normal hunting cartridges. It is proportional to the momentum at the muzzle times the diameter of the bullet. Expressed as a fraction, the Taylor KO Factor is:

TKOF = Mass x Velocity x Diameter divided by 7000
 
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The 410Gr bullet of the .416 Rigby (traveling at 2370 FPS) will outpenetrate the 500Gr bullet of the .458 Winchester Magnum (traveling at 2130 FPS). But the larger diameter bullet of the .458 caliber will impart a greater shock to the game’s central nervous system (assuming that the velocity is still sufficient).

The exception to this rule, is when you’re hunting the great cats. The higher velocity calibers clearly crumple them better due to cats possessing a highly developed central nervous system. So a .416 Rigby is a better choice than a .458 Winchester Magnum but a .458 Lott or .450 Rigby Magnum is better still.
 
As a very big FAN of the 458 Lott not the Win Mag and If I had to choose between 416 Rigby and 458 Win Mag then the Rigby would win hands down.
Why because if you shoot the 416 Rigby with 450gr bullets you make it a total different beast.
With Reloads you will be able to get to 2300fps with 450gr bullet compared to 2150fps and 500gr bullet of the 458.
 
We all know what impact velocity, kinetic energy and ballistic coefficients are, we don't need to discuss them. It depends on what you expect from a cartridge, deep penetration to obtain a very deep wound channel for a quick kill after the first shot or an energy transfer with a greater shock but a more or less deep wound channel to stop above all an animal that is attacking. It is sure that in the first case the cartridge 416 Rigby is an advantage, but that the cartridge 458 Winchester Magnum will certainly have a better stopping effect. If you want to combine both effects, you have to choose for example the cartridge 460 Weatherby Magnum.
 
This could not be any more simple...

Example:
A. With 10 pounds (4.5 kilos) of force pushing a unsharpened pencil (flat surface/meplat .25" (5mm) diameter against their skin, will that penetrate (break the skin)? Probably not.
B. Try the same with a flat meplat shaft of .1" (2.54mm). Does the 10lbs pressure push the smaller diameter shaft through the skin? Maybe with a much better chance than the larger diameter shaft.
C. Decrease the diameter of the shaft to .05". Certainly that will penetrate all but the toughest skin.

If all else is equal such as energy and bullet shape and material, the smaller diameter bullet will encounter LESS resistance to it penetrating.

What I think you are not factoring into the results of dead dangerous game is that with equal energy, the larger diameter bullet will TRANSFER more energy quicker than will the smaller diameter bullet. That is part of Taylor's Knock Out Factor.

https://en.wikipedia.org/wiki/Taylor_knock-out_factor

The Taylor KO factor (TKOF) multiplies bullet mass (measured in grains) by muzzle velocity (measured in feet per second) by bullet diameter (measured in inches) and then divides the product by 7,000, converting the value from grains to pounds and giving a numerical value from 0 to ~150 for normal hunting cartridges. It is proportional to the momentum at the muzzle times the diameter of the bullet. Expressed as a fraction, the Taylor KO Factor is:

TKOF = Mass x Velocity x Diameter divided by 7000
OK so the 416 has a TKO of 57 where as the 458 has one of 70, so you are saying that the 458 is superior?
 
OK so the 416 has a TKO of 57 where as the 458 has one of 70, so you are saying that the 458 is superior?

I think that @Hunter-Habib provided an outstanding answer to this question. Since however you addressed this to me;

Me, no John Taylor long ago figured that all else being equal (energy and bullet design and material), the 416 will penetrate deeper but a 458 will transfer energy quicker, i.e. more energy transfered to animal per unit of measure of travel.

For an elephant brain shot that just misses the brain, the 458 is superior.

For the deepest penetration, the 416 is superior.

The 416 is a better all-around cartridge than a 458, with equal energy and bullet construction.

Plus, a 416 Rigby, Rem, Taylor and so on are dandy 200+ yard cartridges. A 458 Win or Lott for most hunters is not. Yes, a few readers can ring steel with their 458's at 300 or more yards. Good for them. Animals are however not paper or steel targets When one is paying trophy fees for a drop of blood, well as for me, I won't take those shots with my 458's. Plus, the game we pursue deserve a quick death.

As a stopper cartridge in the hands of a PH, a 458 should be better, all else being equal.
 
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I think Michael.458 favors the .458 with a 400 grain CEB

I prefer the recoil of the .458 over the recoil velocity of the .416
 
The reality is that either caliber works fatastically, its 400gr vs 500 gr debate. I personally feel that a 458 win mag can be built on a standard length action and when done right, very easy rifle to carry and use from a practical standpoint. The Rigby is going to require an overall larger rifle....

That said for a "stopper" I think most guys would choose anything 500 gr over a 400 gr. But for universal use and possibly dropping down to a 350 gr in the rigby and really having a rifle that can reach out and light recoil. To "make it into a different beast" as mentioned in a previous post, work up a 450 gr load in the rigby. Another thing to consider is a rifle made for the 416 rigby is probably going to be a very slick operating unit, compared to every 458 I've had experience with, with the belt and more or less straight stick cartridge doesn't seem as smooth rolling through the action of a bolt gun.
 
I’m surprised to hear from some of our experienced members that the 416 will outpenetrate a 458 given momentum and SD favor the 458.

I do defer to real world experience and observation however. The observation that the 416 is a better all-around cartridge - perhaps more versatile is a better description - and the 458 is a better dedicated DG cartridge and ‘stopper’ (if you can handle the recoil) resonates with me.

Interesting topic.
 
Hi CZDiesel,

I have no experience with the 416 Rigby but have had a bit with the .458 Win Mag, having owned 5 and reloaded for all of them...

From what l have read, and from what l have been lead to believe, the problem with the .458 not penetrating sufficiently is when the expected velocity wasn't achieved.
When the desired 2150fps with a 500gn bullet was achieved l have never heard of anyone complaining of it's performance on dangerous game.
In fact, isn't 2150fps with a 500gn bullet the benchmark for DG?

When reloading for the .458 l have never had a problem reaching 2150fps with a 480-500gn projectile.
The highest l have reached with a 500gn projectile is 2220fps and this was from the 24" barrel of my Winchester M70.
I had a custom CZ550 in .458WM with a 21" barrel and l was still able to reach 2150fps with a 500gn Woodleigh. I did this by loading to suit the long magazine of the CZ and using a Lee FCD to crimp the bullet.

I also managed 2100fps with the 550gn Woodleigh and 2300fps with the 450gn Woodleigh Hydro in the .458 Win Mag.
I just can't imagine either of these loads lacking penetration and with modern bullets like the CEB that weigh less - but penetrate more, I could only imagine the .458 Win Mag being more effective than ever...

So l don't know if any of this helps at all but l guess what l'm trying to say is that it's not hard to reach 2150fps with a 500gn bullet out of the .458 Win Mag.
I've done it in all of my .458's I've owned and I'm a nurse - not a PH, so if l can do it anyone can...
And like l said earlier, l've never read of any complaints of the performance of a 500gn bullet at 2150fps on DG...

Russ
That's interesting regarding the 500gr not achieving the 2,150 fps being the suspected culprit for insufficient penetration because when you look at each of today's available factory ammo, not one achieves that velocity from what I can tell.

Hornady DGS/DGX - 2,140 fps (close)
Norma (Solid) - 2,100 fps
Federal TBBC - 2,090 fps
Nosler (Solid) - 2,067 fps
Federal Woodleigh Hydro - 2,050 fps
Federal Sledgehammer - 1,950 fps

Those are also muzzle velocities so impact velocities would be much lower.
 
I had great success with 450 grain bullets out of my 458 Win Mag on Cape buffalo. I didn’t feel under gummed with the 450 grain bullets. I think going forward, with the right bullets, 450 grain projectiles are what I am going to shoot in my 458 Win. As far as recoil goes, I believe this rifle is at my limit in terms of recoil tolerance but I am able to manage it well with practice. I do find that a PAST shoulder pad really helps during range time.
 
But where is the empirical evidence that the 416 penetrates better? I see again a lot of 416 advocates and that’s great and maybe true? But the math doesn’t support it?
So again back to the original question, who can show that the 416 can out penetrate a 458?
@michael458 any insight on this?
Are there any tests that have been done between the two on some type of medium showing this? Because again theoretically the 458 WinMag with its SD and velocity should out penetrate it…

@Northern Shooter I dopplered the 500gr Hornady DGS out of my 22” Winchester and it was doing 2170ftps with over 5200ftlbs of energy, the 500gr DGS did 2150ftps for over 5100ftlbs of energy
 
I do find it interesting that the numbers show theoretically the 458 should provide better penetration but I have also heard over time how great the 416's are for penetration.

I have done some testing in my time that has provided results to suggest SD may not be as important as we think it is. I am a big advocate of using projectiles with a high SD for DG, however there must be a threshold and once you exceed that threshold increasing SD no longer provides any improvement to penetration performance.

I have done some testing with Woodleigh expanding projectiles out of a 458 Lott and Woodleigh expanding projectiles out of a 500 Jeffery. I found SD didn't really seem to make any difference atleast with these specific projectiles and loads used, for example the 500 Jeffery firing a 535 grain RNSN with a SD of .294 provided the same penetration as a 500 grain RNSN with a SD of .341 from the 458 Lott. However the 535 grain projectile from the 500 Jeffery was running at a higher velocity, maybe this made up for the lower SD? Hard to say as there will be a threshold for velocity vs bullet construction as well. I ran some of the 535 grain projectiles at much higher than recommended impact velocities and the penetration decreased significantly, obviously from over expansion on impact.

From what I have seen in the field and testing on the range, SD only seems to make a significant/noticeable difference in extremes, for example a bullet of similar construction with a SD of .25 vs a bullet with a SD of .375 will show a difference in penetration. But 2 bullets with SD at around .3 or above seems to be the sweet spot/threshold for SD and no longer seems to change penetration performance. This has been my experience over the years, others may have seen or experienced different results.....
 
There is a very recent thread where the OP was pondering between a 416 and a 458 and there were many that posted that the 416 will out penetrate the 458…
Now the OP had said that he posted because he wanted both feedback but also because it’s fun to have these discussions. So I thought I’d follow up along the same lines in that let’s keep it fun and informative!

So it’s interesting to me to hear some here say that the 416 will out penetrate the 458? I’ve never heard that before, doesn’t mean it’s not true though?
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… Theoretically this should all lead to not only more penetration but much more damage along the way?
In real use, not theory, my PH told me without hesitation the 458 WinMag, both Dalton and York of the very know Dalton and York Safaris use the 458 WinMag, Kevin “Doctari” Robertson calls the 458 the “Gold Standard”, and Taylor wrote in his book that while the 416 is a much better all around cartridge it’s not a stopping rifle where the 458 is?
Now in all of this penetration is key! So can anyone show where the 416 which has less energy, less momentum, smaller meplat, and less weight can out penetrate the 458?
If you’re referring to ‘Pondoro’ Taylor, his go-to ‘stopping rifle’ was also THE elephant gun in Africa during his era …. Jeffrey’s .404.
 
@michael458 would be the one to confirm here.

I believe I have seen data on the 416 B&M going 60+ inches of penetration and the 458 getting 40+. That said, I'm sure he has done tests on the dame media and can offer more controlled results.
 
I do find it interesting that the numbers show theoretically the 458 should provide better penetration but I have also heard over time how great the 416's are for penetration.

I have done some testing in my time that has provided results to suggest SD may not be as important as we think it is. I am a big advocate of using projectiles with a high SD for DG, however there must be a threshold and once you exceed that threshold increasing SD no longer provides any improvement to penetration performance.

I have done some testing with Woodleigh expanding projectiles out of a 458 Lott and Woodleigh expanding projectiles out of a 500 Jeffery. I found SD didn't really seem to make any difference atleast with these specific projectiles and loads used, for example the 500 Jeffery firing a 535 grain RNSN with a SD of .294 provided the same penetration as a 500 grain RNSN with a SD of .341 from the 458 Lott. However the 535 grain projectile from the 500 Jeffery was running at a higher velocity, maybe this made up for the lower SD? Hard to say as there will be a threshold for velocity vs bullet construction as well. I ran some of the 535 grain projectiles at much higher than recommended impact velocities and the penetration decreased significantly, obviously from over expansion on impact.

From what I have seen in the field and testing on the range, SD only seems to make a significant/noticeable difference in extremes, for example a bullet of similar construction with a SD of .25 vs a bullet with a SD of .375 will show a difference in penetration. But 2 bullets with SD at around .3 or above seems to be the sweet spot/threshold for SD and no longer seems to change penetration performance. This has been my experience over the years, others may have seen or experienced different results.....
This is great info! I hope others can shed more light! Thank you!!!
If you’re referring to ‘Pondoro’ Taylor, his go-to ‘stopping rifle’ was also THE elephant gun in Africa during his era …. Jeffrey’s .404.
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!
@michael458 would be the one to confirm here.

I believe I have seen data on the 416 B&M going 60+ inches of penetration and the 458 getting 40+. That said, I'm sure he has done tests on the dame media and can offer more controlled results.
Just curious, are you asking about the 458Win or is there a 458 B&M?
 

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