Neck sizing to fire form?

[vano]

My 30br brass is all prepped, any need to size before fire forming.

 

[dedogs]

Will they fit the chamber as is? How did you prep them?

 

[vano]

Expanded the neck, cut the length, cut the neck thickness, beveled the inside of the neck.
Every case I tried fit, set two cases with 125 gr. TNT's both seated fine.
They fed fine got some light marks from the lands at the seating depth I used will most likely seat with short jump.
Vano

 

[Sniper338]

I dont think you need to resize before fire forming. Personally i resize after fire forming with my stuff that has to be fire formed.

Cant resize a 6BR case to a 30 br... so resizing is irrelevant until you have 30 br brass..

 

[Brians356]

If you were fireforming "bulletless" no neck expansion or sizing would be warranted. That's another plus for bulletless.

For example, I fireform my 250-3000 Ackley cases "bulletless" from raw 22-250 brass. After that all I'm doing is trimming/chamfering the necks, and sizing them down a few thou with the bushing neck die for seating the 25-cal bullets.