.458 Win Mag, 400 gr. Bullets?

[Wismon]

How effective are 400 gr. bullets in the .458 Win Mag?

As I understand it there is some controversy about the 458 because of it's lack of case capacity, so that makes me wonder: why not use 400 gr. bullets?

Is sectional density so important that a low number negates the effectiveness of a 400 grain bullet? After all, 400 grains is still 400 grains...

What's the scoop?

[Gerard]

400gr Hollow point monos work well in a 458WM. For elephant and buff, use a 450gr mono solid. The two bullets are roughly the same length and leave more than enough case capacity to be very effective. Run the 400gr soft at around 2400fps and the 450gr solid at 2300fps.

[Wismon]

Thanks, Gerard.

A 400 gr. bullet at 2400 fps or a 450 gr. bullet at 2300 fps sounds to me like it would do the trick on anything that walks. I guess I don't understand the controversy behind the 458 Win Mag.

[Indy]

Here was the controversy:

The original intent was to fire a 500 grain bullet at 2150 fps. Why? Because ever since about 1900, it had been understood that that was good for anything that walked the earth.

As it turned out, some of Winchester's ammo, while advertised to do this, would not. Either the powder clumped together when kept in humid climates for 10 or 15 years, the bullet was glued in with glue that melted and ran into the powder, or the Winchester loading machines were improperly set up and a bunch of powder slopped out of the cases. I have heard all three theories.

Anyway, Winchester cut the velocity to about 2000. The .458 Lott was invented to get the original velocity.

Today, with better powder than WW748, no glue (try crimping), and no sloshing out of the case, it's no trick to get 2200 fps with 500 grain bullets. I load 450 grain bullets to 2250 because flat point 450 grain solids will penetrate deeper than round nosed 500 grain soft points, and I don't need any more velocity.

The sectional density of 400 grain bullets is a bit low for penetration on elephants.

As loaded by Hornady, the .458 Lott with 500 grain bullets only gets 50 fps more than the .458 Winchester.

So I don't think there is any controversy any more.

[Wismon]

Indy,

I know all about the official history of the 458. The controversy I was referring to is the likes of how a 400 gr. .45 cal bullet at 2200+ fps is somehow marginal for elephant. No one says that about a 400 gr. .404 or .416 bullet at that or lesser velocities.

Again, is sectional density that important? And if it is, what makes a 450 gr. bullet suddenly adequate?

I have no interest in a .458 Lott, especially when, with a long-throated as-is CZ 550 you can seat the bullets waaay out there…

[Indy]

Wisman,

Here's my $0.02.

A 400 grain bullet in a .416 will penetrate further than a 400 .458 grain bullet because it's longer and skinnier and therefore doesn't encounter as much resistance as a wider bullet of the same weight. In short, the sectional density is better.

Who determines how much sectional density is enough. "Conventional wisdom" says you need more than .300 so that leaves the 400 grain .458 bullet out but lets in the 400 grain .416 and the 450 grain .458. I don't know who that guy "Conventional" is. Probably guys just repeating what they've read.

The only way to prove anything would be to shoot some already dead elephants with various bullets in various places and measure the penetration.

Another variable is velocity. You can probably get at least 2400 with a 400 grain bullet. I have loaded 350 grain bullets to 2600 and 2700 from a 22" barrelled .458. My Winchester has a lot of freebore. As you point out, with a CZ you can do a bit better by loading the bullets out farther.

Incidentally a 350 grain .458 TSX at 2700 has 5700 foot pounds of energy at the muzzle and 3000 at 300 yards.

Another old wives' tail is that a .416 is better than a .458 because, if you encounter plains game, you can shoot it at farther distances due to a flatter trajectory. Well, a .458 400 grain bullet will stay within 3" of a 416 of the same weight out to 300 yards. Run the numbers.

[Hi Ball]

Wismon..... I have shot 350 grain bullets out of my .458 Win mag to 24850fps! I don't have all my figures upstairs with me but I can tell you that a 450 grain bullet out of a .458 Win mag will do 2240fps and that is all that is neccessary for penetration on the bad stuff. It will NOT penetrate as deep as a .416 cal in a 400 grain bullet for a fact.

The .458Win mag with 400 grain bullet is great on just about any animal but I would go another route if hunting something dangerous on the Dark Continent or the biggest of bears. There are several very good 450 grain bullets for use in the .458 Win mag. I have close to 500 rounds (several boxes) of 465 grain bullets for my .458 Win mag and had my Chrony read 2185fps with a 24 inch barrel rifle. PSI using IMR-3031 powder at 77grns powder is "56,800-lbs" My 22 inch barrel .458 reads 73fps less with the same load at 2112fps. Barnes reloading manual states that a .450 grain weight bullet has a Max velocity of 2284fps using H-4198 at 63 grains of powder. H-335 gave a Max velocity of 2249fps using 70 grns or powder......However I do NOT use their reloading manual for my loads.

Now my .458-Lott using the same 465 grn bullet in a 24 inch barrel rifle will Chrony at 2285fps. Now that is "100fps faster" than the .458 Win mag with 24 inch barrel. The PSI for that load is 51,700 lbs. Now as you can obviously see by the figure comparisons, the .458-Lott has less pressure and goes faster by 100fps using a 465 grain bullet in a 24 inch barrel rifle. I figure you will pick up maybe 15 to 25 fps more velocity by using a 450 grain weight bullet.

My .416 Remington magnum will drive a 400 grain bullet to the velocity of 2490fps out of a 24inch barrel! A Squared has a 400 grn bullet going 2482 using RL-15 powder at 82 grains of powder. PSI for this load is 55,100 avg.

I have shot plains game with my .416 Remington magnum (over 40 head) with 325 & 350 grain bullets! Now those 325 grain bullets were going 2775fps with 83 grains of RL-15 powder. The 350 grain bullets did an honest 2640fps out of my model 70 Winchester. ****** "NO .458 Winchester magnum is going to shoot with these two bullet weights and come close to matching the velocity of the .416 Remington magnum".

[Hi Ball]

Hey INDY!!! Say FLYBOY, what you been drinking lately ??? Maybe I can get a little to ease the pain.

Now I got to ask you Indy, when and where did you get a .458 Winchester magnum rifle in 24 inch barrel length, to shoot a 350 grain jacketed bullet to a velocity of 2700fps??? Hell I am all ears!!!

Now I have gotten my .458 Winchester magnum (24 inch barrel) in a model 70 Winchester, which has reached the MAX Velocity of 2536fps and bother that is ALL she wrote. Now most of the reloading manuals I have seen or read, state that 2500fps with a 350 grain bullet is MAXED OUT!!! Please clarify the 2700fps with a 350 grain bullet going 2700fps, for this old man OK.

[Hi Ball]

Indy, yes I know I added a ZERO to the velocity but everybody knows your can't get a .458mag or Lott to go 24,850 feet per second right.

[Indy]

Hi Ball,

Here's how I get 2700 fps with a 350 grain TSX in a 22" barrel .458 Winchester Model 70, as chronographed with a Shooting Chrony Beta. Yeah, I know what the loading manuals say.

First, notice that the 350 grain TSX has three grooves. Use the middle one for crimping, not the front one as in 450 grain TSXs. This gives you more case capacity, in effect, as the Model 70 has oodles of freebore. If you have a CZ550 you can go one more groove and still fit in the magazine, but I have to use the middle one with the Model 70.

Next I figured out that H4198 was a pretty good powder to use with this bullet. I started with 72 grains and loaded one cartridge with it. Then one with 73, one with 74, and so forth until I could not get any more H4198 in the case.

Then I started with the 72 grain load and fired it through the Chrony. Next the 73 grain and so forth. After each shot, I looked carefully at the case. No extractor marks or cratered primer pockets on any of them. None were even slightly sticky or gave reisistance in opening the bolt. Had there been, I would have stopped.

When I got done, I plotted the velocity of each shot on a graph against powder weight. The best fit straight line through these points deviates only a few fps from any particular shot, so now I have a chart showing velocity vs. weight of H4198.

I will not quote the maximum charge on the internet, but suffice it to say that I ran out of case capacity before I maxed out the load. I backed the maximum off one grain and got 2690, which is about 2700 at the muzzle because the Chrony was about 15 feet ahead of the muzzle.

I was hoping that the 350s would shoot higher than 450s, so I could have a "long range" load and a buffalo/elephant buster without changing the sights. Unfortunately, my 2600 and 2700 fps 350 grain loads shoot LOWER, by a lot. About all I can figure out is that the 450 grain bullet stays in the barrel longer while the barrel is recoiling upward.

AA2015 might give better velocities than H4198 but I have not tried it.

According to the JBM ballistics program, and using a BC as measured by someone I know, not the one Barnes publishes, a 350 grain TSX sighted 3" high at 100 yards will be less than 7" low at 300. It has 3000 foot pounds of energy at 300 yards. What I was trying to do is to make the storied 3-gun battery into a 1-gun battery.

Nobody ever tries this because "everyone knows" that big bores like the .458 are not accurate enough for long range shooting. Why? Maybe because .450 doubles with iron sights weren't very accurate in 1900. But my .458 is as accurate as any good hunting rifle, at least the few times I get the courage to shoot it with good bench technique.