Resize 450/400 3 1/4 to 450 3 1/4?

analog_peninsula

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Is there any functional reason why I shouldn’t try to run the 450/400 brass through the 450 expander? Inquiring minds want to know.
 
Is there any functional reason why I shouldn’t try to run the 450/400 brass through the 450 expander? Inquiring minds want to know.
That's a pretty big expansion that might split the cartridge case neck. Better aneal that very well.

A better path may be to first aneal the case necks then fire form using a small charge fast burning powder and some type of lightweight filler in lieu of a projectile.
 
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I agree with Mark A on the procedure.
Other than a split case give it a go.
There are people who resizing 308 win up to 375 to create the 375 Raptor.
Most likely the thickness of the brass will dictate if it would work reliably.
 
Is there any functional reason why I shouldn’t try to run the 450/400 brass through the 450 expander? Inquiring minds want to know.

Not sure if it will work. You'd probably want custom sizing dies to step it up 3x gradually, annealing as you go. As Wyatt stated, not sure if you'll have the needed length.

Maybe much easier is just getting 450NE brass? It would save you a thousand bucks on special dies. 450/400 3.25" is more valuable, harder to find brass than the 450NE brass anyway.
 
If your 400 3-1/4" brass is headstamped you shouldn't have any problem swapping it for some correct 450NE brass.
I'd trade some...
 
It will probably come out short, not sure if that will be an issue for you
Being a flanged cartridge, would not matter to much. Kinda like the 38 special 357 magnum.
The 500 grain bullet could be seated longer if the neck would support it.
The bullet would have a pretty long jump to the rifling.
My buddy who shoots cowboy action occasionally gets a 38 special in his 357 brass. While not idea of good reloading procedure he does load the 38 special to 357 length and shoot it.
 
Being a flanged cartridge, would not matter to much. Kinda like the 38 special 357 magnum.
The 500 grain bullet could be seated longer if the neck would support it.
The bullet would have a pretty long jump to the rifling.
My buddy who shoots cowboy action occasionally gets a 38 special in his 357 brass. While not idea of good reloading procedure he does load the 38 special to 357 length and shoot it.
As long as it doesn’t need to be crimped in the groove.
 

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