Military

PGU-27A/B TP/ PGU-28A/B SAPHEI / PGU-30A/B TP-T

The 20mm Improved Cartridge Family projectiles have an optimized aero ballistic shape that reduces time of flight and increase velocity at range for increased probability of hit. The Multipurpose Concept PGU-28A/B Semi Armor Piercing High Explosive Incendiary (SAPHEI) with delayed reaction carries the effectiveness inside the threats including light armor, aircraft, vehicles and general support equipment. The 20mm SAPHEI PGU-28A/B has demonstrated reliability and operability in the M61 gun system tests completed by the U. S. Government. The Target Practice, PGU-27A/B and Target Practice-Tracer, PGU-30A/B are cost effective training cartridges that are ballistically matched with the PGU-28A/B.

The US 20mm PGU-28/B SAPHEI (semi-armor piercing high explosive incendiary) projectile was developed in the mid 1980s (replacing the U.S. M-56A3 HEI projectile) for use in the air-to-ground role due to its armor penetrating capability. Since it provided significant performance improvements in terms of drag, effective range, time of flight, and graze angle tolerance, the round was selected for use against air-to-air targets in gunnery scenarios.

The PGU-28/B is the only projectile currently used by the Air Force and Navy for fixed wing air-to-air combat. This projectile is fired from the M61A1 gun system that is utilized by the F-14, F-15, F-16, and F/A-18 aircraft. Current plans call for use of the PGU-28/B with the M61A2 gun system on the F-22 aircraft.

The improved 20-mm (PGU) configuration ammunition for the M61A1/A2 aircraft guns is issued in the form of cartridges (fig 7-5). All service cartridges have matched ballistics and are electrically primed. Initially procured ammunition is not graded, and all accepted lots are serviceable for issue and use in applicable weapons.

The improved 20-mm (PGU) configuration ammunition for the M61A1/A2 aircraft guns is issued in the form of cartridges. All service cartridges have matched ballistics and are electrically primed. Initially procured ammunition is not graded, and all accepted lots are serviceable for issue and use in applicable weapons. The M103 brass cartridge cases are marked longitudinally or circumferentially with the caliber/case designation on the first line. The manufacturer symbol is on the second line. The interfix number, lot serial number, and year of manufacture are on the third line.

All PGU-configured cartridges are loaded with ball spherical propellant WC 867. M52A3B1 Electric Primer The electric primer is used in all current PGU configurations. It consists of an open-ended brass cup that contains a brass button insulated from the cup by a plastic liner. The firing pin of the gun contacts this button. The ignition charge (a conductive explosive mixture) is in contact with the other side of the button, and is retained by a paper disk and a metal support cup. The electrically initiated primer ignites the propellant charge. The primer explosive element is sensitive to electromagnetic and electrostatic energy.

All projectiles have essentially the same external configuration. The rotating band is copper alloy swaged into a circumferential groove near the aft end of the steel body. Ammunition type is identified by the color the projectile is painted and by the lettering on the body of the projectile.

PGU-27/B Target Practice (TP)

The PGU-27/B projectile consists of a steel body with a solid aluminum nosepiece swaged or crimped to the steel body. This cartridge has no explosive filler in the projectile. The cartridge is used in practice firing, for boresighting of weapons, and testing of new guns. The projectile shape and ballistic properties are similar to those of other PGU configuration ammunition.

PGU-28/B Semi-Armor Piercing High Explosive Incendiary (SAPHEI)

The PGU-28/B projectile consists of a steel body with an internal cavity filled with a sponge Zirconium pallet, composition A-4 and RS 40 incendiary mix. The aluminum nose contains RS 41 incendiary mix and is swaged to the steel body. This cartridge is for use against aircraft and light material targets, and functions with semi-armor piercing, high explosive, and incendiary effect.

PGU-30/B Target Practice-Tracer (TP-T)

The PGU-30/B consists of a steel body with an aft cavity containing the tracer pellet. The aluminum nose is swaged or crimped to the steel body. Tracer A tracer pellet is loaded into a cavity machined in the base of the TP-T projectile used in the assembling of the PGU-30/B cartridge. The heat and pressure of the propelling charge ignite the tracer pellet. The tracer is visible for approximately 3.2 seconds during projectile flight. This cartridge is virtually the same as the PGU-27/B projectile, except it incorporates a tracer in the base of the projectile.

On January 24, 1997 Primex Technologies (formerly Olin Corp.), Marion, Ill., was awarded a $12,278,365 firm fixed price contract for 429,500 20mm PGU-27/B cartridges and 878,000 20mm PGU-28/B cartridges. Work will be performed in Marion, Ill., and is expected to be completed by Dec. 31, 1997. Contract funds will not expire at the end of the current fiscal year. This is a sole source contract initiated on Aug. 27, 1996. The contracting activity is the U.S. Army Armament, Munitions and Chemical Command, Rock Island, Ill. (DAAA09-97-C-0016).

General Dynamics Ordnance and Tactical Systems, Marion, Ill., was awarded on Dec. 14, 2001, a $9,411,616 modification to a $1,686,112 firm-fixed-price contract for 20 millimeter PGU-28A/B cartridges. Work will be performed in Marion, Ill., and is expected to be completed by Oct. 30, 2002. Contract funds will not expire at the end of the current fiscal year. There was one bid solicited on Dec. 10, 2001, and one bid was received. The Operations Support Command, Rock Island, Ill., is the contracting activity (DAAA09-00-C-0001).

The Joint Live Fire Program (JLF) program was chartered by OSD in March 1984, to conduct Live Fire Testing of fielded US and foreign air and ground weapons platforms and munitions. In the fiscal year 2001 Air Systems Program, JLF testing addressed the vulnerability of the CH-47 Chinook, C-130 Hercules, F-16 Fighting Falcon and the lethality of the U.S. 20mm projectile PGU-28/B against selected foreign targets.

While the PGU-28/B represents an improvement in aerodynamic performance, its lethality (damage capability given a hit) against actual aircraft targets has not been demonstrated. Detailed plans were prepared to test the lethality of the PGU-28/B against a Soviet MIG-29 aircraft and a MIL-24 Hind Helicopter. The tests were conducted in FY02. With approximately 8,000,000 PGU-28/B rounds in the inventory, these tests will have a broad impact.

General Dynamics, Marion, Ill., was awarded on Sept. 1, 2006, a $13,710,629 modification to a firm-fixed-price contract for 20mm PGU-28A/B SAPHEI cartridges. Work will be performed in Marion, Ill., and is expected to be completed by July 31, 2008. Contract funds will not expire at the end of the current fiscal year. There were three bids solicited on April 5, 2005, and three bids were received. The U.S. Army Sustainment Command, Rock Island, Ill., is the contracting activity (W52P1J-05-C-0073).