I want to poll everyone on their favorite big bore caliber that will be used to hunt in Africa and maybe some game such as bear, moose and elk here in North America. I may leave out some calibers, so if I miss one, let me know.
I own two types of .458 and they have both been to Africa and all over North America.
The 26 inch barrel .458 win mag loaded with 510 solids or round nose can take anything on this planet out. 510 grains at 2460 fps went clear through a 9'6" brown length wise. One shot drop on cape buffalo and forbrained a large bull elephant. I've Chronoed custom 275 grain hollow point at 3000 fps.
The other equally fun gun is my .458 American. Very deadly with 405 grain barns -X's loaded to 2380 fps
.270 Ackley improved 29 inch 1.250 dia. target barrel 7mm STW 28 inch 1.250 target barrel. I also love my .458 mag for varmints and the biggest game in the world.
Well , it depends on what your gonna be shooting in Africa if you going after the big five that I would say at least a 458Win.
I persoanly have a 460 Wby that I got a good deal on so I got it but I'm not totaly convienced that all that power is needed. the bigest thing I have shot was a domestic hog that got loose and had turned feral she weighed over 600lbs and one round at about 125-150yds in the head fliped her over. Bullet exited the rear quarter leaving about a fist sized hole , she never even kicked .
the bullet was a 500gr Trophy Bonded Bear claw launched at about 2600fps.
If you chose the right bullet I think that the 378Wby would be a good choice but you bullets may not be well suited for all game
Personally, if you are going to go big, go big. I use a custom 500 A-Square, McMillen stock, McGowen 26" barrel, on a P-14 action. 600 grain dead tough. Pet load is 118.5 grains of H-4895, chrono is 2527fps with an ES so far of 33fps. Have only tested it on hogs so far, but has been unreal to this point. Off the bench, I consistantly get 1"-1.25" groups at 100 yards.
Technicly most of what you've listed are "medium bores". Others to consider are...
458Lott (probably the most practicle, as 458WM can also be used in it, factory ammo is available)
458 Hubble Express (can also use 458 WM and Lott ammo)(plinking loads are 325gr @ 3200fps)
700 Hubble Express (50BMG case streightened out and belted)
I should have listed the 458, but in my opinion, anything that the 416s can do, the 500s and 600s and 700s can do with a greater amount of recoil. When picking out one of these rounds, I feel that there is a limit where reasonabilty ends and ooverkill begins. I agree with what you said about the 458 lott. If I knew how to alter the poll, I would put that and the 458 win in there. One other thing is round availabitliy just in case ammo is lost on the way to Africa.
Well, this is turning into another one of those you need bigger as that is always better topics.
Onfortunately, no one has considered teh North American aspect of your question. Certainly this rifle should be designed for African big game but to be honest, it will probably be used much more here at home so I feel you should choose a round that will work for both very well.
Now the big 458s and 475s and 500s are great and if you need to stop a foght with a pissed off cape buffalo or elephant, bigger is generally better if you can shoot the cannons.
That said, most bad situations are a result of either poor shot placement or poor bullet performance. A PH would much rather see their hunters carrying a 375 H&H or a traditionally loaded 416 Rigby then a 378 Wby or 416 Wby and certainly a 460 class round. Simply because they realize that its that first shot that can either end the fight very quickly or result in a very serious situation.
Every cartridge you list is adiquate for heavy game in Africa even without the 458 caliber rounds and larger.
Hands down the most useful over the widest range of hunting would be the fast 375 rounds. With proper bullets they will cleanly harvest the largest game with a properly placed bullet.
THey offer much more ranging ability then the larger bores and they are much better suited for North American game. Still, if your going to build a rifle for use on heavy or dangerous African game I would simply recommend the 416 Rigby as it will do anything you need it to and have plenty of power as well as boing easy to shoot which means you will actually shoot it more and become better with it.
You can also load it with 350 gr bullets for use in North America and have a big bear rifle with no peers. They work very well on elk and moose as well.
While you could use the 458s here at home, they are far out performed by the smaller bores in trajectory which can be an issue here at home.
For an all around heavy game rifle in Africa and here at home, the 416 Rigby would be a very hard round to beat. The 416 Wby is also in this same class but velocity should be dropped to around 2500 fps with a 400 gr bullets for better bullet performance.
If you like the 416 Rigby can also easily be loaded up to 2700 fps with a 400 gr bullet just like the Wby in a modern rifle. It is a much more friendly round loaded to 2400-2500 fps though.
Just my opinion, leave the true big bores and get one of these 416s. It will serve you well.
Also, ammo availability is very good in Africa.
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