Mikecr
Well-Known Member
This is incorrect.
Process annealed necks are softer and provide less tension. Fully annealed provides zero tension.
Outward spring back from downsizing of harder necks causes lower seating forces, but this doesn't necessarily mean less tension. In fact if interference fit is still 1thou+ with harder necks that sprung back more to that 1thou, these harder necks will produce higher tension(regardless of seating forces).
Same with crimping. This causes higher tension no matter what, and as Bart mentioned, it results in greater variance.
What process annealing does for us is reduce neck tension, and therefore variance in tension(provided annealing was done consistently correctly). That's a good thing if your load likes it, and bad otherwise. Some cartridges/loads need high neck tension, so annealing would be undesired there.
There seems only half the best neck sizing going on with the collet die. That is, it's missing expansion.
If it included this, the necks would be squeezed in ~1thou more to a smaller mandrel, and then an expander would bring necks outward, where they would spring back INWARD(instead of outward) to the correct interference fit. With this, given that spring back continues over time, tension would grow over time instead of decreasing.
Best neck expansion is with an expander mandrel. IMO Lee could easily improve their design by incorporating expansion with their mandrels.
This is another reason I use bushings, and Sinclair's expander mandrel system.
As to managing brass hardness itself, that should be another thread.
