Thread: Rebore.

Originally Posted by whanahuia

I believe that's called Pushing.

Potato, potatoe, semantics.

I believe JES are the go to, but I don't know how easy it would be to do the trans border thing with gun parts.

Most barrel blank makers pull the buttons

Some push
Tony Hawkins machine had an ingenious pusher for his buttons

Some home tinkerers push buttons with a massive hydraulic ram
It can work to make a sort of serviceable pistol barrel
Most likely will turn to shit with a long rifle barrel

The amateur on line ones I've seen were just relying on the in built twist on the button to get their twist rate.

The professional buttoned barrel makers have a sine bar controlling the twist as well and can often speed up or slow down the twist a few inches either way.
Depending on the grind of the specific button