Big Bore Loads For 458 Win. Mag. Against Grizzly

358Scout

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WILL IT DO THE TRICK?
First of all, I roll my own. I do not hunt big game. I love to target shoot and go fishing. I bought this rifle because I just wanted a big bore - this one came up and I couldn't resist. I've owned assorted custom built units but nothing compares to lobbing a 500gr Barnes at 1700fps at a target 100 meters away giving me 3/4 inch groups. Here's the dilemma. I've had arguments with friends who claim it just isn't enough to take a grizzly - that I need more power to have that size bullet penetrate that much hair, hide, fat, bone etc to make a kill let alone go through and through. I'm convinced this enough. I mean I'm not taking on a Cape Buffalo. Grizzly is the largest N. American carnivore and I am sure this will do the trick. People take buffalo with black powder and lead bullets of the same weight and their only going 1100 - 1300 fps. Any one have suggestions?
 
500gr @ 1700 is pretty light in the whole scheme of .458wm loads. The Hornady book has listings from 1950 - 2200fps for the 500gr buggers (sorry, don't have the barnes here).

That being said, your friend is still incorrect...that's a tremendous amount of energy that'll hammer straight through pretty much anything close enough. People have been killing grizzlies for decades very comfortably with 300gr RN's going out of a 45-70 slower than that.

The .458wm is an elephant cartridge that could body slam a grizzly, cape buffalo, or anything else with proper shot placement.
 
Even if you slow the 500 down to 1200 fps it will still completely penatrate and kill a griz. If you handload try the 350 hornady 63-70 grains of 4198 at 2300-2500 fps alot better for North America, and shoots quite flat.
 
Hi...so if and arrow through the lungs kill a bear in 20-40 yds why will a 500 gn moving at 1500-2000 fps not kill a bear.
Sometimes I wonder where these friends come from "Streets of New York"?
Don
 
Thanks. I have a box of factory 500gr magnums. After 5 shots you develope a massive headache. The 350 either the Speer or Hornady brands do not give me any consistent groups smaller than an inch. I'm kind of a perfectionist. One gun nut at a gun show told me the rifling of a 458 was designed for the 500 gr. When I change to that I will see the difference. He gave me a hand full of Barnes triple shocks. He was right. I can shoot this all day and well you should see what it does to gophers.
I'm pleased and thank you for your comments.
 
Your friends don't know #### about bears if they think a 500 grain bullet at 1700 won't penetrate. 2000 FPS would be much better but not mandatory.
 
here ask the bears friend the moose what a 500 grain slug can do under 50 yards out of a 458 :owned:
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gawd I luv that pic lmao

edited to adddddd..... TELL your so called friends that a 458 is the worst bear gun ever a 300WSM is way better just ask this grizz
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oh yea shot with a 220 grain round nose hornaday @ 150 yards BUT a 500 grain slug just wouldnt do .......
 
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"...friends who claim it just isn't enough to take a grizzly..." What do they think you need? Just curious. Mind you, no bullet gives a 100% guarantee of a one shot stop on any game.
What are you loading with? Barnes indicates 1800 + fps is the starting load velocity for either of their 500 grain bullets. No energies given. Just curious about that too.
 
I watched my dad shoot a 450gr barnes tsx max load out of his big brno 458 win mag, knocked his glasses right off... good enough for me! wouldnt want to be on the other end of that operation, whether I was was a 1000lb grizzly or a 700lb moose
 
SUNRAY: Developed loads using assorted powders IMR 4759, Reloader 7, IMR 4895 and IMR 3031. My first concern was group size followed by recoil. Once I graduated to the 500gr bullet everything seemed to fall into place and there were less trips to the range. Actually 3 trips to the range. Because all loads in manuals are damn near full power house loads, I resorted to a 45-70 load. Having read this cartridge could be loaded to different pressures depending on the type of rifle used, I narrowed it down to this.

Hornady manual ( for 45-70) with 44.1 grs of IMR 3031 equals 1487 fps with a JRN bullet. The Barnes manual ( 458 Win Mag) with 68.0 grs. of IMR 3031 equals 2140 fps. Averaged it out and started with 55.0gr of 3031 - group had shrunk to just under 1 1/4". I decided to lessen the next load to 50.0 grs. and work up and down from there. The first 3 shots made one clover leaf hole a hair over .75". I was so excited I sent flyers here and there. You can take the head off a gopher at 100 meters. I did try lead bullets but the groups were terrible even with gas checked bullets. And cleaning - it was to time consuming. All I know is the loads I have now are the only caviar this rifle will see and perform with. I did a test on 14 phone books. Clean through - dug the bullet out of the berm which penetrated another 12" of dirt. The bullet did not mushroom much which I'm assuming is due to the fact there was no moisture to fully create a hydro effect as when it passes through actual body mass of 90% fluid. Thats about it....
 
The .458 has been used with great success on some of the most dangerous animals in the world. Anyone who thinks it's not enough for thin skinned dangerous game is living in denial.

There were problems associated with the .458's performance in Africa but it had nothing to do with the actual cartridge or bullet. What happened is that some African game agencies bought .458 rifles for elephant control work, and when they bought the rifles, they also bought a large consignment of ammunition. This ammo was stored in very hot conditions over many years and this caused the ball powder to loose its zip. After some close calls, testing was done and some of the rounds chronographed 300 fps below the velocity of newly manufactured ammo. While a 500 gr solid at 2150 is not the most powerful round in the world, it gets the job done in a predictable manner, something not true of the .375. Many considered the .458/500 at 2150 perfect for the world largest game, and when Winchester developed the .458 it copied the proven ballistics of much older cartridges like the .450 #2 Nitro Express.

For bear work in North America, the load should be chosen based on what it is to be used for. A light pointed jacketed bullet is better for the hunter due to its higher velocity and trajectory flattening shape. For protection work the best bullet available is MT Chambers hard cast 480 gr WFN. This bullet loaded on the warm side of 2100 fps is a close range stopper of the highest order, and will reach out to get the job done at 150 yards. The .458/450 gr X bullet works too, but it adds nothing in performance and costs 5X as much. The hunter could choose a lead core 350 gr jacketed bullet loaded to 2400 fps, and have a few 480's in his pocket incase he is unlucky enough to have to dig his bear out of a stand of willows.

Although I don't currently own one, I am a .458 fan. I've also had a lot of fun at my pal Pounder's expense. He sets store by his .458 Brno 602. When the discussion switches to guns and loads I just sadly shake my head and tell him that any straight wall cartridge shorter than 3" is for pistols. I was going to have an 8" TC Contender built in .458 just to prove it to him, but didn't. I must have got to him too, that rifle now has a Lott chamber!
 
I did try lead bullets but the groups were terrible even with gas checked bullets. And cleaning - it was to time consuming.

I have observed very good accuracy with the MT Chambers hard cast 480 gr WFN in both .458 and .45/70 rifles. I think black powder shooters would disagree with your observations. Firing a few jacketed bullets takes care of any leading in the bore, although hard cast bullets don't foul excessively.
 
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I have observed very good accuracy with the MT Chambers hard cast 480 gr WFN in both .458 and .45/70 rifles. I think black powder shooters would disagree with your observations. Firing a few jacketed bullets takes care of any leading in the bore, although hard cast bullets don't foul excessively.

Lead is pretty much like a hard point(not good), Maybe get fair results with BHN 16 , but why , go get some modern bullets in the 350-425 grain range.
Check what folks are using in Africa on Lion, and add a few grains of bullet weight:D
 
358scout I own a 458 American chambered rifle, which Frank Barnes thought would be a great idea for North American 'dangerous game' back in 1962.
Some of the loads you quoted, 55 & 50 grains of IMR3031 under 400ish weight bullets work/shoot very accurately in my shorter wildcat version of your factory cartridge. If you feel you must increase velocity, Re7 should be your ticket with most bullets. And as Boomer stated there are many wonderful cast loads to choose from, as long as they are of adequate hardness and weight and reliably feed/eject/extract through your rifle. I found with this cartridge of mine, adequate crimping must be ensured as the heavy bullets may, more easily work themselves loose if jolted to much, without an adequately strong crimp, that will not reek havoc with inconsistant velocities, thereby causing split groups on target & such.
I did find though, that many of the longer bullets (more weight/more bearing surface) tended to be more accurate as a rule within loading spec's. Thankfully this style of bullet design is easily found in most .458 bullet choices, be they jacketed or heavy cast lead. As noted previously by others, nothing wrong with hard cast lead WFN (wide flat nosed designs) and Garrett Cartridges [visit thier website] use these predominately in thier 44 magnum and 45/70 products. They have a great reputation world-wide BTW. Although they do not sell 458 Winchester Magnum cartridges, this is very close in concept to your personal choice.
You have a great stopper rifle there, that most persons cannot handle due to recoil forces.
You are indeed well armed sir!
 
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Lead is pretty much like a hard point(not good), Maybe get fair results with BHN 16 , but why , go get some modern bullets in the 350-425 grain range.
Check what folks are using in Africa on Lion, and add a few grains of bullet weight:D

That's communist propaganda designed to over throw our way of life.:D

If we look back to the days of black powder rifles, .458 velocities and cast bullets were the rule, and the buffalo hunters and those who explored the wilderness of Africa and Asia did very well with cast bullets that penetrated deeply, and left large wound channels due to their flat nose profiles. More recently, high velocity rifles and expanding bullets have never caught on for very large African game, and if a non-expanding flat nose bullet kills the largest game on earth, it should do likewise on lesser game. I certainly had no trouble killing thin skinned African game with flat nosed solids from a .375.

The .458's velocity lends itself very well to the use of cast bullet, but a WFN profile has proven to be a better killer than a pointed bullet. If you'd be willing to pay for a 21 day lion safari in Tanzania, I would be happy to run some tests. Maybe I can find this guy again . . .

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According to those with far more knowledge than I, the preference for big cats is a high velocity bullet that grenades once inside. The old .375/260 gr Ballistic Tip would be a good choice. Cats, even large ones are lightly boned, where as bears tend to be heavy and dense, thus a stronger bullet is more appropriate. Given the number or bears killed with 12 gauge slug guns, a .458 loaded with a lead bullet is leaps and bounds ahead in performance.


Here we see a couple of recovered 450 gr TSX's with a 480 gr hard cast WFN sans gas check. I doubt very much that an animal killed with the TSX would not be killed as quickly with this cast bullet given similar impact velocities. Due to the powder capacity of the .458, a muzzle velocity of 2100 is about its limit with bullets weighing 450-500 grs.

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Checked out MT Chambers site. I think I will try out a box of his extra Hard 458's. Sent him an email. He's only an hour north of here. Thanks for all you input. I feel much better now.
 
I so hope your friend is right. I can't seem to talk my wife into letting me buy a .50bmg and now I've finally found my excuse.

Let's just hope I don't shoot him in the paw.
 
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