has the title says
I only shoot cast in my 4570 and now I have coming a winchester safari express in 458
I am looking at Redding for the tight spec
or do you have a better choice

You will find the SAAMI .458 Winchester Magnum to be the best of all possible cast bullet shooters.

What you have for case mouth belling and neck expanding of the .45-70 Govt. will be useful for the .458 WinM.

I have and use die sets from RCBS, Lee, Redding, and Hornady.

The Redding belling plug is too short and will leave you with a wasp waisted loaded round.
And you are right, it may size the case body a little tighter, not needed.

The RCBS is the best 3-die set except for the bullet seating plugs they supply.

The Lee seater plug is best of all shapes, will handle any bullet nose from bluntest to pointiest.

And the Lee Factory Crimp Die is a must.

I also bought some over-sized expander plugs that fit in a Lee die, up to .461" diameter,
and powder compression plugs for BP loads,
from either Track of the Wolf or Buffalo Arms Co., or both.
They work for all my .45-cal BPCR needs too.

NB: Best to have a set of RCBS dies and a set of Lee dies, including the Factory Crimp die.
I would need those to do all that I do with cast bullets in the .458 WinM.

Size your bullets to .461" for the .459" groove of the Winchester M70.
The bigger and harder alloy, powder-coat painted, cast bullets I make are passed through a .460" Lee bullet-sizing die, and they spring back to .461".

Soft lead .459" diameter, grease-lubed bullets for the smaller-grooved .45-70 Govt. seem to shoot well in the .458 WinM if you keep velocities down to 1400 fps.

Hard-alloy, PC-painted, .461-inchers with gas checks are accurate to 2200 fps.
Any faster may be more than the bullet can tolerate on impact, IMHO.


.458 Winchester Magnum Perfection
Nota bene: In maxima potentia parvum spatium.
Id venit et vicit omnis.
The longer load plus higher pressure is a Lott of fun.
But three point three four and sixty thousand will get it done,
if the rifle is chambered for the four five eight Winchester.
Believe the Three Mahohbohs, or you're a monkey's sister.

thank you
been shooting 458 and 4570 for years
have at least 20 different mold .... factory and custom
expander plug up to 460
sizing die to 461
even got a wad punch die
realy eager to shoot
getting more interested in powder coating also

Welcome, I might add this to THE MISSION, for more mileage there.