45/70 Lee Loader to load 458 Win Mag?

[aephilli822]

Same diameter boolit, right? Since it only neck sizes couldn't I make a .405 spacer and use the Lee Loader kind of like using a 38 Special die adjusted short in the press to load 357 Mag?
Thoughts, opinions, dire warnings of injury, death, and failure?

[Green Frog]

I don't know about the Lee Loader, but my old time go-to 310 dies from Lyman would probably work quite well. That's what I would try (and of course, I already have the Lyman dies! ) Please note that I have not tried this, but in the situation you describe, I wouldn't hesitate to try that strategy. YMMV

Froggie

[Oklahoma Rebel]

isn't the 458 win mag belted? if you had a lathe to account for that I bet it would work, not sure how the modification would effect using the 45-70 cases in it, I think it would be alright... not sure Travis

[Hardcast416taylor]

For what you could buy a set of correct dies for and then be safe and correct, I would go that route.Robert

[EDG]

The best was to find out is try it.
Every one here can speculate. Those that have no skin in the game might tell you anything.
About the only way that you can blow yourself up is by putting in the wrong amount of propellant, the wrong propellant or the wrong bullet.

Same diameter boolit, right? Since it only neck sizes couldn't I make a .405 spacer and use the Lee Loader kind of like using a 38 Special die adjusted short in the press to load 357 Mag?
Thoughts, opinions, dire warnings of injury, death, and failure?

[blikseme300]

What rifle are you loading for? Recently got my first 458WM, a 1975 Ruger M77, and am having fun casting, loading and shooting it. I'm using Hornady dies and a Lee collet FCD for load assembly. So far good results using a Lee 450gn over SR4759.

[country gent]

I would look in several loading manuals, cartridges of the world or at sammi chamber drawings first check several things case thicknesses, body tapers, and any shoulders or steps between the 45-70 and 458 win mag cartridges It may work fine with the ring you propose provide the above are close.Taper may be the stumbling point over working the the 458 mag brass. Look at dia at just infront of belt and just behind bullets base and ahead of rim and just behind bullets base on 45-70. This will show the body taper in each case. Be safe and do the research before jumping in. A split case from over work to much expansion isnt any fun