.458 Win Mag Shotshell Loads

[MedRiver]

I am working on putting a .458 WM together. Just playing with some ideas and thought it would be fun to put together a shotshell load for shooting grouse off the trail. Anybody done this or have some data or suggestions for the best way to go about it?

Any input is appreciated

Thanks

 

[Boone66]

I would try 410 data, or black powder loads. Either with a over shot card and roll crimp or fold the edges of the shell a little over the over shot card and then water glass to seal it, maybe mylar wrap the shot also, or use a wad for steel. The pattern will be in a doughnut pattern, because of the rifling. If your putting a muzzle brake on, have a additional one made with straight rifling, 2 or 3in long, it will stop the shot spin and you can either have it made with or without a choke. You may need to make your wad stack, because 410 is a bit small for a 458 shell. Anyways, that's how I would approach it.

 

[MedRiver]

Thanks. No brakes planned for this rifle.

 

[Boone66]

Ok, then when you pattern it, you will have to figure out where to put the center of the doughnut, so the outside of it hits the head.

 

[SRvet]

Would be good for snakes! I had this thought too

 

[Red Leg]

Must be worried about really big snakes - rat shot from a 38 is pretty effective a very close range.

Rifled barrels are terrible at producing patterns. It is why the Paradox was such an amazing creation when developed a little over a hundred years ago.

 

[SRvet]

When I considered it I thought it might be useful if a cobra stumbled into camp unexpectedly when a .38 was not close to hand !

 

[Boone66]

Must be worried about really big snakes - rat shot from a 38 is pretty effective a very close range.

Rifled barrels are terrible at producing patterns. It is why the Paradox was such an amazing creation when developed a little over a hundred years ago.

Yep, which is why I suggested a straight rifled screwed on choke. Even if no brake is used and only a tread protector, it would help develop a pattern, that much better then a doughnut.

 

[Riflecrank]

MedRiver,
Excellent show of flexibility for the Magnificent .458 WIN MAG.
Here is a simple recipe and two shots patterned at 10 yards.
I used #7-1/2 shot but you can get heavier shot loads and better patterns with #8 or #9:

Some more details, basically this is a 28-ga payload, no mere .410 shotgun:

Some tools for handloading:

 

[Riflecrank]

Yet to be tested for pattern, almost a 20-Ga payload using protruding shot capsule taper crimped over
the main payload of loose shot beneath it.

 

[Riflecrank]

Naysayers have not tried it, I'll bet, dollars to donuts.
The above patterns were shot with a factory Whitworth .458 WIN MAG (23.6" barrel length) that was awaiting rechambering to .458/.416 Ruger because it had a rough chamber from the factory, outwardly beautiful though it was.

 

[BeeMaa]

As @Red Leg mentioned earlier, rifling in a barrel will have a negative effect on the pattern. The reason for this is the spin imparted to the shotcup by the rifling will have the effect of spreading the shot soon after leaving the barrel. This would make patterns at 30 yards very inconsistent.

The .410 caliber or 28 bore would be a better choice for this endeavor with a cornucopia of factory loaded ammunition available without having to wildcat a 458WM shotshell.

Want a real challenge? Find a 32 bore shotgun and work up some loads for it.
https://www.shotgunlife.com/shotguns/gordy-and-sons-rizzini-quail-gun.html

 

[Red Leg]

MedRiver,
Excellent show of flexibility for the Magnificent .458 WIN MAG.
Here is a simple recipe and two shots patterned at 10 yards.
I used #7-1/2 shot but you can get heavier shot loads and better patterns with #8 or #9:

View attachment 707026
View attachment 707027
View attachment 707028View attachment 707029

Some more details, basically this is a 28-ga payload, no mere .410 shotgun:

View attachment 707030

Some tools for handloading:

View attachment 707031

View attachment 707032

My 120 year old paradox shoots 4 shots LxR/LxR with 740 gr bullets into 2.5" at 100 yards and throws perfect modified 1 1/8 ounce No. 6 shot patterns at 40 yards. This .458 load would be useful for ........... ?

 

[mgstucson]

I think these loads would be good snake medicine at 10 yards, and birds close up. Stateside, I would just carry 5 410's in a revolver made from 9.3x74r brass blown out straight. I don't think I want to try to carry a handgun through customs going or coming through Africa. I would not do this on a regular basis in my 458, but I might stick a few shot rounds in my pocket on an African trip "just in case.".

Thanks for sharing all the info.

 

[Boone66]

I think these loads would be good snake medicine at 10 yards, and birds close up. Stateside, I would just carry 5 410's in a revolver made from 9.3x74r brass blown out straight. I don't think I want to try to carry a handgun through customs going or coming through Africa. I would not do this on a regular basis in my 458, but I might stick a few shot rounds in my pocket on an African trip "just in case.".

Thanks for sharing all the info.

444 marlin cases work for solid brass 410 shells also

 

[mgstucson]

444 marlin cases work for solid brass 410 shells also

Those work great too. 444 = 2.225" 9.3x74 = 2.93" That is almost 3/4" more shot. It is a heck-uv-a snake charmer out to about 7 yards. I have killed a lot more rattlesnakes with a shovel than a firearm. I am just glad I don't have to get that close anymore. I don't react as quick as I used too. They don't either after I "charm'em."

 

[Riflecrank]

As @Red Leg mentioned earlier, rifling in a barrel will have a negative effect on the pattern. The reason for this is the spin imparted to the shotcup by the rifling will have the effect of spreading the shot soon after leaving the barrel. This would make patterns at 30 yards very inconsistent.

The .410 caliber or 28 bore would be a better choice for this endeavor with a cornucopia of factory loaded ammunition available without having to wildcat a 458WM shotshell.

Want a real challenge? Find a 32 bore shotgun and work up some loads for it.
https://www.shotgunlife.com/shotguns/gordy-and-sons-rizzini-quail-gun.html

The 10-yard patterns were done without the usual plastic cup wads.
Loose shot going down the bore might cause some leading, but it is not much spread by rifling twist.
Magnum shot at low velocity is not going to leave much lead behind.

Medriver just wants to be able to shoot a grouse or ptarmigan out of a tree along the trail.
#8 for birds.
#9 for rats and snakes.

 

[Riflecrank]

I think these loads would be good snake medicine at 10 yards, and birds close up. Stateside, I would just carry 5 410's in a revolver made from 9.3x74r brass blown out straight. I don't think I want to try to carry a handgun through customs going or coming through Africa. I would not do this on a regular basis in my 458, but I might stick a few shot rounds in my pocket on an African trip "just in case.".

Thanks for sharing all the info.

That is the idea, you get it, unlike Red Leg.

 

[Riflecrank]

Boone66,
Do you have a smoothbore 444 Marlin.
If not, you are in same boat as a rifled .458 WIN MAG.

 

[Riflecrank]

Those work great too. 444 = 2.225" 9.3x74 = 2.93" That is almost 3/4" more shot. It is a heck-uv-a snake charmer out to about 7 yards. I have killed a lot more rattlesnakes with a shovel than a firearm. I am just glad I don't have to get that close anymore. I don't react as quick as I used too. They don't either after I "charm'em."

I must admit that shot shell loads are the only advantage the .458 Lott has over the .458 WIN MAG.
0.3" more length of birdshot charge.