45-70 case length.

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Lumpy Grits
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Joined: Tue Jan 28, 2003 7:58 pm
Location: Springfield, Missouri-U.S.A. Earth

Re: 45-70 case length.

Post by Lumpy Grits »

Size that brass, and check the OAL.
Any over 2.100 trim back to 2.095.

G.
"Hav'n you along, is like loose'n two good men"
bruce m
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Joined: Tue Aug 04, 2009 5:25 am
Location: australia

Re: 45-70 case length.

Post by bruce m »

jack,
fired cases from your chamber would ideally measure 2.102" long or a bit more.
when you size them, they will become longer, but will shorten to that when you light the fire.
this is where having a bullet diameter that slides into a fired case is good for accuracy.
and it avoids case length issues in the transition.your chamber seems not to be a saami one, as it has freebore.
this is less than ideal for pp bore diameter bullets.
the freebore needs to be filled with bullet, and the bore dia is way under that.
a good chamber for greasers, as it allows the bullet to seat out, giving more powder capacity.
this chamber would suit groove diameter pp bullets, seated out to touch the rifling, more than bore diameter, if you are really chasing accuracy.
the best solution to your problem is to have a dual diameter mould made, where the part of the bullet in the case and the freebore added together is one diameter which is a sliding fit, and anything in front of that patches to bore diameter.
put an elliptical nose 1.5 calibres long on the front and you will have the perfect bullet for that gun.
casting the bullet to those dimensions faces the fact that that is what the rear of that bullet will become dimensionally before it starts to move.
as the freebore is, a bore diameter bullet will be floating in mid air there when the round is chambered.
this bullet will solve both the case length issue as well as the accuracy issue that comes with ill fitting bullets should you want not to shoot patched to groove.
keep safe,
bruce.
ventum est amicus meus
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