Ok did a quick check. The neck on a fire formed 40-90 bn from my Shiloh is right at .6 long, a fired 40-65 case is 2.19, doing a close visual , the 4065 case mouth would be supported in the neck portion of the bn chamber... So yeah a 40-65 liner would work,, but just barely.

the most expensive bullet there is isn't worth a plug nickel if it don't go where its supposed to.
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