BFJ,

I dont know why you would call a forend lever a "screw type"? I think you are getting the action mixed up the other parts of the rifle, look up on Hallowell & Company for the different terms, its a great reference.

As far as I know there are 3 major types of forend releases, the Anson push button, Delely (sp) lever and the Lever release ( or as I've always heard it called the "Rigby style forend lever")

Maybe someone here with more experence than me can clarify.

Ed