Gun muffler and noise abatement system for large caliber gun

In a gun muffler for a large caliber gun having a gun tube, said gun muffler comprising a transition section fitted around the gun tube and engaging the gun tube, a main pressure vessel having a first end attached to said transition section and defining a main pressure chamber of about 4,000 cubic feet, an extension pressure vessel disposed in series with and connected to said main pressure vessel and defines an extension pressure chamber of about 1,000 cubic feet, at least one orifice plate being adjustable relative to at least one of said main pressure vessel and said extension pressure vessel and being disposed in at least one of said main pressure chamber and said extension pressure chamber, and a catcher disposed within at least one of said main pressure vessel and said extension pressure vessel for entrapping particulates and for permitting the projectile to pass, wherein the improvement comprises said catcher comprising a plurality of columns adapted for being removably attached within said main pressure chamber near the connection of said main pressure vessel to said extension pressure vessel;

• wherein said columns are in a generally parallel arrangement and at least two of said columns are staggered relative to one another with respect to the direction along a central axis of said pressure vessel.