Quote Originally Posted by thorarinna View Post
I know from rod building that the blanks are hollow all the way.

Thorarinn.
My understading is that you cannot buy a blank that is not plugged.

These blanks are hollow as they come out of the oven and off the mandrel. BUT they are then plugged on the male end at the factory. It prevents crushing of the male side of the ferrule when placed into the female side. But it also allows a vacuum, to develop only in individual sections. I would not try to drill out the plug. That is for a tip over butt ferrule. For spigot ferrules, the spigot is the plug.

The rod builder doesn't do it, they come that way.