If I understand the procedure correctly the case moves up, over and just past the expander ball. You stop right there and the internal dimension of the case neck is +/- the diameter of the expander ball. When the ball is pulled back thru the neck it is not expanding the neck any further, just traveling thru the corridor it just expanded. ??
“When Tyranny becomes Law, Rebellion becomes Duty”
Colossians 3:17 (New King James Version)
"And whatever you do in word or deed, do all in the name of the Lord Jesus, giving thanks to God the Father through Him."
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