I bought 3 boxes of Hornadey .458 win mag “Heavy Magnum†ammo at a resent gun show and was wondering if anyone had chronographed any of this ammo. I find it interesting that Hornady claims a muzzle velocity of 2260 fps. This must be one long barrel maybe 36 in. I don’t have a .458 at this time or I would try some over the coronagraph. I suppose I could shoot it in one of my Lotts but the velocity would be slightly less. I am just wondering how much slower than advertised it really is.
Bill

Here are the velocities I got.

22" Barrel = 2,089 fps.
24" barrel = 2,133 fps.

465H&H

I got velocities consistently in the 2,150 fps out of my CZ .458 Lott with the factory 25-inch barrel.

A couple of years ago I shot them through my .458 Lott with a 24" barrel and got an average of about 2160 fps. Not too bad IMO. they were only about 60 fps behind the Hornady .458 Lott soft points. Most factory stuff I've tested (except Buffalo Bore's ammo) seems to lag well behind the advertised velocity.

Out of the same CZ on the same day, Hornady Lott ammo all ran right at or around 2,300 fps in both softs and solids.......

2210fps out of a 24" M70. Good stuff!

I got 2,175 fps out of a M-77 Ruger "Tropical" rifle with a 24 inch Magna-ported barrel.

Just to put this out for the sake of the thread-

I'm not likely to purchase a box of this ammunition to test it, but I will take three or four rounds from anyone here and run it through my .458win Whitworth for chronograph testing purpose, happy to post the results on this thread for all to see.


--Tinker

Thanks for the info. The velocity’s reported are what I expected 2260 is pretty hot out of a 22-24 in barrel. I was thinking they might have come up with a supper powder to get that kind of velocity with safe pressure.
I think it is iterating that if you didn’t know which of the posted velocities were from a Lott and not just a .458 you wouldn’t be able to tell. The normal spread of velocities between different rifles even by the same maker is more than the difference of shooting 458 win mag in a Lott.
Bill

Bill-

This is why I offer the unmodified barrel of my 458win Whitworth and chronograph for anyone interested in another velocity report from a rifle chambered in 458win, not the lott.


--Tinker

there you guys go, you have just smashed the holy grail of the .458 clan! can of worms openned...Its a fine round at those velocities btw...

You are absolutely right Ray.
We often forget the real reason for the .458 LOTT. The driving intent was to have a round that did 2150 with a 500 gr bullet with lower pressure than the .458 Win mag of the day. The fact that you can hot rod it with today’s powder is a secondary benefit.
I can remember back in the early 70’s shooting some 458 win mag that was only making about 1850 fps with large variations shot to shot. I wish I had all my old records they would be fun to compare to today’s ammo.
That being said the .458 Win Mag is a much better cartridge today than when it was borne in 1956.

Thanks for the offer Tinker but I don’t want to shoot this up it will be on my table at the next Market Hall gun show in Dallas.
Bill

If I can recall correctly, Jack Lott loaded the .458 Lott hot from its inception. I don't think he was just trying to get 2,150 fps. Correct me if I am wrong. I know it was an attempt to cure the shortcomings of the win mag, but I think he loaded it hot........

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