Here is picture of 4bore/ga action with lever open and
breach down.You see bottom of breach block.The action
and barrel will be held in stock with 2 bolts into bottom
of action one bolt in barrel ahead of action and a recoil
barrel ring in front end of stock. Didn't have to add
any recoil lugs, as the wide back of the action is
the recoil lug. This is now called the Hubel Falling
Block Action. Second picture is of the 4bore cases
and 2000gr slugs, with 20mm case I make 4bore/ga cases
from and the 30-06 for comparison.Ed