[nhbob1]

I seem to recall reading that they were making some of these deep penetrator bombs using old artillery barrels for the casing. Not sure if those were one off proof-of-concept tests or if those were production.

[Axenolith]

Iowa class battleship gun tubes. I think the used them in GWI

[xone]

I seem to recall reading that they were making some of these deep penetrator bombs using old artillery barrels for the casing. Not sure if those were one off proof-of-concept tests or if those were production.

Initially used the old barrels but new production has purpose built cases, GBU-28