45-90 Dies

[1972RedNeck]

Will Hornady 45-70 dies work for 45-90?

If not, will Redding 45-90 dies work for 45-70?

[44 AMP]

While considered a "straight" case the .45-70 does have a small amount of taper. Book specs show it going from .480" at the mouth back to .505" at the base. Case length is given as 2.105".

The .45-90 shows .479" at the mouth and 5.04" at the base, case length is 2.4"

SO, which the dimensions given are close they are not exactly the same. However, since the specs given are usually the max and sizing dies are made to resize the cases to slightly below min specs, it might work.

With a .45-70 die, backed off the right amount, you would essentially be "neck sizing" (and possibly some of the case body) your .45-90 brass.

flaring, seating and crimping would work normally, with the .45-70 dies adjusted up the right amount to compensate for the different case length of the .45-90 brass.

The other way around isn't as good. .45-90 sizer might size .45-70 well enough but I can't say for sure that it will. There should be enough adjustment in the expander stem and the seating stem to do .45-70 but again, I can't say for sure if there will be or what die sets might, or might not have that much range of adjustment.

Crimping .45-70 using a .45-90 die isn't going to work. The shorter .45-70 case will not reach the crimp shoulder of a .45-90 die.

In short, if you raise .45-70 dies the .3" needed, it MIGHT work. The other way around might size and seat but won't crimp.

[mehavey]

As above... properly adjusted and barring really excessive pressure blowing out the web dimensions of the case,*
45-70 dies will work on 45-90 cases just fine.
(trust me )

* not an expected issue with anything close to normal 45-90 pressures

.

[mehavey]

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