458 win mag minimum bullet weight for Cape buffalo

[RR 314]

Have you tried the 420gr Raptors and 450gr solids? Those 420s are also devastating on buffalo and would penetrate from any angle without having to be so careful.

I just bought some 420 Raptors for a .450 Rigby heading my way. I was speaking to a friend and he voiced his displeasure at shooting anything under 500 grains in any .458. I assured him I would be just fine. . . and the buffalo will not be fine.

 

[IvW]

Quick easy answer....... More......

BUT........ all other factors of solid penetration must be equal before SD has any true effect........

A #13 500 gr Solid at 2300 fps will penetrate deeper than a 450 gr at 2300 fps with all other factors equal.............. A 550 #13 Solid at 2300 fps will penetrate deeper than a 500 gr at 2300 fps......... and so on and so on............. Pure Science .......

However, sometimes Science does not meet reality....... you must get all factors equal in the real world, and that is not always possible. And at this point some of the other Factors begin to edge other factors out.

Cool....as I am busy developing a 420gr 404 Jeff brass solid. I am leaning towards 75% meplat but am also thinking of trying a cavity 45 degree shoulders in the meplat. Need maximum penetration but also want more "damage" for buff and lion. This rifle will be used for dg foot safaris and only solids are permitted. Elephant is always the greatest threat but buff and lion can occasionally cause problems.

 

[michael458]

Cool....as I am busy developing a 420gr 404 Jeff brass solid. I am leaning towards 75% meplat but am also thinking of trying a cavity 45 degree shoulders in the meplat. Need maximum penetration but also want more "damage" for buff and liin. This rifle will be used for dg foot safaris and only solids are permitted. Elephant is always the greatest threat but buff and lion can occasionally cause problems.

No doubt about it, 75% meplat will cause more damage and trauma up front, you are on the right path for that. The issue may be feed/function with that larger meplat.

We know for a fact, that .458 caliber +, a 65% meplat of caliber will actually self stabilize itself during terminal penetration, even without any twist rate, or extremely too slow twist rate. We also know for fact that 65% to 70% is optimum for depth of penetration....... below 65% you start to have stability issues, and above 70% depth of penetration starts to diminish because of meplat size..... you trade a little depth for more trauma basically........ but with a good nose profile 75% meplat still gives you all the depth you would need anyway.

I limited the meplat size on the #13 Solids to 67% and we went 68% on the North Forks (John at North Fork just had to be a little different..LOL) This was primarily feed/function in Winchester M70 Control Feed guns. I found if we went to 70% or slightly better, we started having some issues feed/function, by dropping to 67% and 68% meplat feed/function is 100% in M70 Control feed guns. So that is where we are, and the fact that we did not want to drop further for terminal stability.

I am a little lost on 45 degree shoulder part.... but not a concern I don't think?

If you can get your bullet to 75% in .423 caliber and it feed/function, then it will definitely enhance your up front hitting ability and will still give you plenty of good straight line penetration....... In the smaller caliber you might be able to pull it off.... .416 to .423............. Keep us posted, that might be a great development for the smaller calibers...........

 

[IvW]

By 45 degrees I basically mean "drilling"/machining a cavity with 45 degree angle into the front of the meplat. Excuse my lack of correct terminology.....like a cup point....

 

[ldmay375]

No doubt about it, 75% meplat will cause more damage and trauma up front, you are on the right path for that. The issue may be feed/function with that larger meplat.

We know for a fact, that .458 caliber +, a 65% meplat of caliber will actually self stabilize itself during terminal penetration, even without any twist rate, or extremely too slow twist rate. We also know for fact that 65% to 70% is optimum for depth of penetration....... below 65% you start to have stability issues, and above 70% depth of penetration starts to diminish because of meplat size..... you trade a little depth for more trauma basically........ but with a good nose profile 75% meplat still gives you all the depth you would need anyway.

I limited the meplat size on the #13 Solids to 67% and we went 68% on the North Forks (John at North Fork just had to be a little different..LOL) This was primarily feed/function in Winchester M70 Control Feed guns. I found if we went to 70% or slightly better, we started having some issues feed/function, by dropping to 67% and 68% meplat feed/function is 100% in M70 Control feed guns. So that is where we are, and the fact that we did not want to drop further for terminal stability.

I am a little lost on 45 degree shoulder part.... but not a concern I don't think?

If you can get your bullet to 75% in .423 caliber and it feed/function, then it will definitely enhance your up front hitting ability and will still give you plenty of good straight line penetration....... In the smaller caliber you might be able to pull it off.... .416 to .423............. Keep us posted, that might be a great development for the smaller calibers...........

We do know the .458, 380 grain Lehigh copper WFN solid has a sweet spot range for COAL, to feed in most 458 Winchester bolt rifles. That meplat is .346 for this .458 bullet. I think this is about a 75.5% meplat.
A radiused nose edge would possibly help it feed a with a slight bit more COAL tolerance range. Though, this bullet is intended for 45-70 lever rifles. I don't see a little edge radius effecting that aspect either.

 

[michael458]

By 45 degrees I basically mean "drilling"/machining a cavity with 45 degree angle into the front of the meplat. Excuse my lack of correct terminology.....like a cup point....

OK OK, I am with you now, I know what you mean........... Yes, basically making a brass Cup Point... a good thing, would be stronger than copper, would not be as prone to deform...... My friend Sam made some of these similar to what you are talking about, I believe they were for his 500 NE....... might have been .585 caliber too...

We do know the .458, 380 grain Lehigh copper WFN solid has a sweet spot range for COAL, to feed in most 458 Winchester bolt rifles. That meplat is .346 for this .458 bullet. I think this is about a 75.5% meplat.

Do you remember what we tested those in? 458 B&M?? I remember we gave them a go, but I forgot, probably the B&M....... Might have been that 20 inch 458 Win? But I did not really put it to feed/function tests..... just terminals.........

I loaded the rest of those Lehighs in 45/70 recently.............

 

[ldmay375]

OK OK, I am with you now, I know what you mean........... Yes, basically making a brass Cup Point... a good thing, would be stronger than copper, would not be as prone to deform...... My friend Sam made some of these similar to what you are talking about, I believe they were for his 500 NE....... might have been .585 caliber too...


Do you remember what we tested those in? 458 B&M?? I remember we gave them a go, but I forgot, probably the B&M....... Might have been that 20 inch 458 Win? But I did not really put it to feed/function tests..... just terminals.........

I loaded the rest of those Lehighs in 45/70 recently.............

I believe the penetration test was 9/14/22, with the 458 B&M.
Edit: the same day testing the 400 gr #13 solid.
You did do load pressure with both the 458 Winchester & Lott.

 

[IvW]

OK OK, I am with you now, I know what you mean........... Yes, basically making a brass Cup Point... a good thing, would be stronger than copper, would not be as prone to deform...... My friend Sam made some of these similar to what you are talking about, I believe they were for his 500 NE....... might have been .585 caliber too...


Do you remember what we tested those in? 458 B&M?? I remember we gave them a go, but I forgot, probably the B&M....... Might have been that 20 inch 458 Win? But I did not really put it to feed/function tests..... just terminals.........

I loaded the rest of those Lehighs in 45/70 recently.............

Any test results? Want to go in the same direction with the 500 Jeff......600gr bullet same design.....