# US 8,783,155 B2 · Stacked projectile launcher and associate methods > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,783,155 B2 - Document ID: US8783155B2 - Status: Granted - Kind: B2 - Application number: 13/148,264 - Filed: 2010-02-08 - Published: 2011-12-01 - Granted: 2014-07-22 - Earliest claimed: 2009-02-06 - Assignees: Metal Storm Limited - Applicants: Daniel William Green - Inventors: Daniel William Green - Web page: https://patentgrep.com/patent/US8783155B2 ## CPC - F41A 21/12: Cartridge chambers; Chamber liners (F41A3/74, F41A9/46, F41A21/04 take precedence) - F41A 1/06: Adjusting the range without varying elevation angle or propellant charge data, e.g. by venting a part of the propulsive charge gases, or by adjusting the capacity of the cartridge or combustion chamber {(adjusting the range by using gas-relieving ports in the barrel F41A21/28)} - F41A 21/10: Insert barrels, i.e. barrels for firing reduced calibre ammunition and being mounted within the normal barrels - F41A 21/28: Gas-expansion chambers; Barrels provided with gas-relieving ports (F41A1/06, F41A13/08 {and F41A21/36} take precedence) - F41F 1/00: Launching apparatus for projecting projectiles or missiles from barrels, e.g. cannons (F41F3/00 takes precedence); Harpoon guns - F42B 5/035: {the cartridge or barrel assembly having a plurality of axially stacked projectiles each having a separate propellant charge} - F41A: FUNCTIONAL FEATURES OR DETAILS COMMON TO BOTH SMALLARMS AND ORDNANCE, e.g. CANNONS; MOUNTINGS FOR SMALLARMS OR ORDNANCE - F41F: APPARATUS FOR LAUNCHING PROJECTILES OR MISSILES FROM BARRELS, e.g. CANNONS (smallarms F41C); LAUNCHERS FOR ROCKETS OR TORPEDOES; HARPOON GUNS (functional features or details common to both smallarms and ordnance, mountings therefor F41A; projecting missiles without use of explosive or combustible propellant charge F41B) - F42B: EXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION (explosive compositions C06B; fuzes F42C; blasting F42D) ## Abstract Provided is a barrel insert for use with a barrel containing a plurality of axially stacked projectiles. The barrel insert has a proximal and a distal end, the distal end adapted to engage a proximally disposed projectile disposed in the barrel. The barrel insert also defines an expansion volume for propellant gases for launching the proximally disposed projectile at a predetermined velocity. ## Claims ### Claim 1 A barrel insert for use with a barrel containing a plurality of axially stacked projectiles, the barrel insert comprising: a proximal end; and a distal end, the distal end adapted to engage a proximally disposed projectile of the plurality of axially stacked projectiles disposed in the barrel and including a wall across the distal end of the barrel insert, the barrel insert defining an expansion volume for propellant gases for launching the proximally disposed projectile at a predetermined velocity, wherein the expansion volume is in part defined by a proximal side of the wall. ### Claim 2 (depends on 1) The barrel insert according to claim 1, wherein the distal end includes a circumferential groove adapted to engage a clip on the proximally disposed projectile disposed in the barrel. ### Claim 3 (depends on 1) The barrel insert according to claim 1, wherein the expansion volume is defined in part by a chamber within the insert, a distal end of the chamber including the wall and the insert including at least one aperture in communication with the chamber. ### Claim 4 (depends on 3) The barrel insert according to claim 3, wherein the at least one aperture is disposed in the proximal end of the insert. ### Claim 5 (depends on 1) The barrel insert according to claim 1, wherein a portion of the proximal end of the barrel insert extends from the barrel, in use. ### Claim 6 (depends on 1) The barrel insert according to claim 1, further including a breech closure for closing the breech of the barrel. ### Claim 7 (depends on 1) The barrel insert according to claim 1, further including a spigot extending from the proximal end. ### Claim 8 (depends on 7) The barrel insert according to claim 7, wherein the volume extends into the spigot. ### Claim 9 (depends on 8) The barrel insert according to claim 8, further including a rear portion attached to an end of the spigot, the chamber extending through the spigot and into the rear portion. ### Claim 10 (depends on 1) The barrel insert according to claim 1, wherein the barrel insert includes a compressible seal adjacent the proximal end. ### Claim 11 (depends on 1) The barrel insert according to claim 1, wherein in use the propellant gases communicate with the expansion volume defined by the proximal end side of the wall only from the proximal end of the engagement with the projectile. ### Claim 12 (depends on 1) The barrel insert according to claim 1, wherein the distal end includes a nose having a shape matching a shape of a nose of the projectile. ### Claim 13 (depends on 1) The barrel insert according to claim 1, further comprising a pillar for supporting the distal end in position, a flange toward the proximal end of the pillar, and a spigot surrounded by a compressible seal on the proximal end of the flange. ### Claim 14 A method of firing a plurality of axially stacked projectiles from a single barrel, each projectile associated with a discrete selectively ignitable propellant charge, the method including the steps of: stacking the projectiles axially in the barrel, the barrel and projectiles together defining discrete expansion volumes for each propellant charge, providing a volume behind a wall across the barrel behind the rearmost projectile in the barrel, said volume predetermined to be larger than the expansion volumes defined for the other projectiles to minimize muzzle velocity variation between the rearmost projectile and the other projectiles in the barrel; and firing the projectiles sequentially. ### Claim 15 (depends on 14) A method according to claim 14, wherein the step of providing the volume includes the step of inserting a barrel insert including the wall into the barrel to locate the rearmost projectile in a predetermined position in the barrel. ### Claim 16 (depends on 14) A method according to claim 14, wherein the step of providing the volume includes the step of providing a barrel closure including the wall behind the rearmost projectile, wherein the barrel closure at least partially defines the volume. ### Claim 17 A method of configuring a stacked projectile launcher, the launcher having a barrel with a plurality of axially stacked projectiles, each projectile associated with a discrete selectively ignitable propellant charge, the barrel and projectiles together defining discrete expansion volumes for each propellant charge, said method including the step of providing a volume behind a wall across the barrel behind the rearmost projectile in the barrel, said volume predetermined to be proportional to the expansion volumes defined for the other projectiles to minimize muzzle velocity variation between the projectiles when each propellant charge is ignited. ### Claim 18 (depends on 17) A method according to claim 17, wherein the step of providing the volume includes the step of inserting a barrel insert including the wall into the barrel to locate the rearmost projectile in a predetermined position in the barrel. ### Claim 19 (depends on 17) A method according to claim 17, wherein the step of providing the volume includes the step of providing a barrel closure including the wall behind the rearmost projectile, wherein the barrel closure at least partially defines the volume.