Pivot-load powder actuated tool with firing chamber insert

A powder actuated tool comprising:

• (a) a housing member;
• (b) a barrel assembly mounted on said housing member for reciprocal movement between breech open and breech closed positions, said barrel assembly having a bore with a muzzleward end and a breechward end;
• (c) a breech block assembly mounted in said housing member, said breech block assembly being slidable in said housing member and spring biased toward the tool muzzle, said breech block assembly including a breech face;
• (d) a firing chamber member slidably mounted in the breechward end of said barrel assembly bore, said firing chamber member having a shank portion extending into said barrel assembly bore, said firing chamber member shank portion having at least one circumferential empty turbulence gas sealing groove formed on the outer surface thereof proximate the muzzleward end of said firing chamber member, said gas sealing groove providing means for preventing substantial breechward movement of said firing chamber member with respect to said barrel assembly when a cartridge is fired in said tool.

A powder actuated tool comprising:

• (a) a housing member including a handle portion and a muzzleward cradle portion;
• (b) a breech block reciprocally slidably mounted in said housing member;
• (c) a barrel assembly mounted in said housing member for reciprocal movement between a breech closed position and a breech open position, said barrel assembly including a bore extending therethrough;
• (d) lug means disposed in said housing member cradle portion;
• (e) slot means disposed in the outside surface of said barrel assembly, said lug means being slidably disposed in said slot means, said slot means including longitudinal slots for providing longitudinal sliding movement of said barrel assembly with respect to said housing member, and circumferential slots for providing axial twisting movement of said barrel assembly with respect to said housing member;
• and
• (f) a tubular firing chamber member slidably mounted in a breechward end of said barrel assembly bore, said firing chamber member comprising a shank portion extending into said barrel bore with said shank portion having a substantially smooth exterior surface save for empty gas turbulence sealing groove means disposed on said firing chamber member shank exterior surface proximate the muzzleward end of said firing chamber member, said sealing groove means being operable to prevent substantial breechward movement of said firing chamber member with respect to said barrel assembly when a cartridge is fired in said tool, said firing chamber member contacting said breech block when said barrel assembly is in said breech closed position, and said barrel assembly being free of direct mechanical connection with said breech block.

A powder actuated tool comprising:

• (a) a housing;
• (b) a barrel mounted in said housing for reciprocal movement between a breechward cocked position and a muzzleward uncocked position;
• (c) a shroud mounted on said barrel;
• (d) means biasing said barrel in the muzzleward direction with respect to said shroud;
• (e) securement means interconnecting said shroud and said barrel, said securement means comprising a slot formed in the exterior surface of said barrel and a stop mounted in said shroud and extending into said slot, said stop being reciprocally slidable in said slot during reciprocal movement of said barrel in said shroud, said slot including a medial enlarged portion providing a camming surface for engaging said stop upon twisting of said shroud with respect to said barrel when said barrel is in said cocked position, said stop being operable upon engagement with said camming surface to cam said barrel in the muzzleward direction and out of said cocked position to prevent air fire of the tool.