458x2 American

[creophus]

I'm in need of some load data for a 458 American (458x2). I have 385gr cast bullets, and various powders including, Varget, IMR 4031 and H4031SC. Anyone have any load data I can use?

I don't want super hot loads as I'm just starting out with this rifle, but it should be able to to handle any safe load since it's a Mauser 98.

[Bullshop]

Supplement data for the 450 Marlin

[Mk42gunner]

I would look at data for the .45-70 and .450 Marlin for starting loads. Case capacity may be slightly less with your gun, but should be close enough for starting loads.

I know I have seen published loads for a .458x2 somewhere, I just cannot remember where right now.

Robert

[swheeler]

The owner of this site shots one, maybe Ken will ring in. 45Nut

[creophus]

Thanks guys. I appreciate the responses. Just had a learning experience: The 300 Win Mag Brass that I cut to 2.1" does NOT side down through a 458 Win Mag die. I guess I should have already known that...

I don't want to cut down my 458 Win Mag brass for this project.

[lotech]

There is some old data ( jacketed & cast) in Wolfe's "Wildcat Cartridges", volume 2.

[chboats]

My 458x2 has a long throat so I seat the boolits out long. The over all length is longer than the listed 45-70 loads in the manuals. Because of the long length I use 45-70 data as a start point. The great thing about 45-70 data is that there is data for every pressure range due to the variety of rifles. If your are shooting shorter boolits up to 400 grain the wall thickness is less of a problem. I use mostly Winchester 338 brass cut to 2" for most loads. If you want to try 500+ boolits the best brass I have found is Winchester 264 win brass. The walls are thin enough to not create a problem. Tried some Remington 7mm rem mag and 300 win mag brass but the walls were too thick for even 300 grain boolits. After all that, the wall thickness can be fixed with a reamer. I was lucky that when I first started shooting the 458x2 I acquired a good supply of both 338 and 264 brass. Have never lost a single piece of brass from case failure.

don't cut off your 458win mag brass until you figure out about the wall thickness.

Even though they are strait wall I still had to fire form the brass due to the taper

Carl

[creophus]

My 458x2 has a long throat so I seat the boolits out long. The over all length is longer than the listed 45-70 loads in the manuals. Because of the long length I use 45-70 data as a start point. The great thing about 45-70 data is that there is data for every pressure range due to the variety of rifles. If your are shooting shorter boolits up to 400 grain the wall thickness is less of a problem. I use mostly Winchester 338 brass cut to 2" for most loads. If you want to try 500+ boolits the best brass I have found is Winchester 264 win brass. The walls are thin enough to not create a problem. Tried some Remington 7mm rem mag and 300 win mag brass but the walls were too thick for even 300 grain boolits. After all that, the wall thickness can be fixed with a reamer. I was lucky that when I first started shooting the 458x2 I acquired a good supply of both 338 and 264 brass. Have never lost a single piece of brass from case failure.

don't cut off your 458win mag brass until you figure out about the wall thickness.

Even though they are strait wall I still had to fire form the brass due to the taper

Carl

Thanks Carl, that makes sense. I really don't want to cut my 458 Win Mag brass because I have a 458 Win Mag that I need them for! This rifle has a chamber big enough for the 458 Win Mag, but because it's so much lighter than my other 458 Win, I planned to shoot 458x2 through it exclusively. May end up light loading the 458 Win Mag cases.

What did you have to do to get 300 Win Mag brass to resize? I got two cases stuck inside my 458 Win Mag sizing/decapping die, WAY before the primer was punched out.

What you say about wall thickness makes sense, but I'm surprised I couldn't size down the 300 Win Mag brass. When trying to get the case out, I lifted my whole loading bench off the ground. I used PLENTY of lube, but that case was stuck TIGHT as can be. The good news is that the mouth of the case was sized down.

[chboats]

creophus - If I got this right you want to shoot a 458x2 in a 458 Win Mag. If that is the case there would be a very long jump to the rifling. I think you would be better just shooting 458 Win Mag brass with reduced loads. I am not sure why you couldn't re-size 300 mag brass after it had been cut down in the 458 Win Mag die. I have a RCBS case forming die that reforms the brass and is a guide for cutting it down to 2". It sounds like a failure of the sizing lube. Try a lanolin based lube. It has always worked for me when reforming brass like 30-06 to 7.65 Argentine where the shoulder is pushed back almost 1/2 inch.

For load data for reduced loads for the 458 Win Mag check the Lyman Cast bullet handbook number 3 or 4. They have loads down to 1300 fps using Unique or 2400. The Lyman Cast bullet no.4 list loads in a 45-70 using Varget down to 45 grains at 11000 psi with a 385 gr boolit.

Carl

[creophus]

creophus - If I got this right you want to shoot a 458x2 in a 458 Win Mag. If that is the case there would be a very long jump to the rifling. I think you would be better just shooting 458 Win Mag brass with reduced loads. I am not sure why you couldn't re-size 300 mag brass after it had been cut down in the 458 Win Mag die. I have a RCBS case forming die that reforms the brass and is a guide for cutting it down to 2". It sounds like a failure of the sizing lube. Try a lanolin based lube. It has always worked for me when reforming brass like 30-06 to 7.65 Argentine where the shoulder is pushed back almost 1/2 inch.

For load data for reduced loads for the 458 Win Mag check the Lyman Cast bullet handbook number 3 or 4. They have loads down to 1300 fps using Unique or 2400. The Lyman Cast bullet no.4 list loads in a 45-70 using Varget down to 45 grains at 11000 psi with a 385 gr boolit.

Carl

You've got some good points Carl. I decided to just go with 458 Win mag loads. I put some Trailboss under a 385gr bullet and will shoot it soon to see how it performs.

[Bull Shoals]

Creophus,
My 458X2 was Built after reading about in Rifle Magazine issue # 19. Buily on a Rem 350 Rem mag action, it had a 21" bbl full length Fajen stock. Brass was cut down 458 Winchester loaded with 49 gr 4198, Win primer and 400 gr Speer jacketed bullets. Didn"t have a chrono then but believe they were pushing 2000 fps. I relate this only to give an idea as to what you can expect. Very accurate with some groups approaching 1".

[creophus]

Creophus,
My 458X2 was Built after reading about in Rifle Magazine issue # 19. Buily on a Rem 350 Rem mag action, it had a 21" bbl full length Fajen stock. Brass was cut down 458 Winchester loaded with 49 gr 4198, Win primer and 400 gr Speer jacketed bullets. Didn"t have a chrono then but believe they were pushing 2000 fps. I relate this only to give an idea as to what you can expect. Very accurate with some groups approaching 1".

Thanks, that's good to know.