The manufacturing of the traditional case demands a powerful inner and outer compression for a double aim:   - push (B) the material inner reinforcement piece towards the rim of the head brass. In this way, it makes a ring tooth and tights the combination tube/reinforcement piece/head brass in a single element resistant to mechanical longitudinal and radial stress coming from the powder deflagration and - shape the diameter (A-A') and the head brass rim with tolerances enabling a perfect functionality into the chamber weapon.   It is obvious that the structural needs required by this processing exclude the possibility to shape, as one likes, the inner reinforcement piece of the base and prevent the construction and the use of profiles balistically efficacious.