5.56mm (5.56 x 45 mm) Ammunition DESCRIPTION 5.56mm center-fire ammunition is issued in the form of a complete round, A complete round (cartridge) consists of all the components (cartridge case, bullet or shot, propellant powder, and primer) necessary to fire the weapon once. Machine gun ammunition is linked by a disintegrating metallic split-linked belt for firing. The M27 link is a reduced size of the M13 7.62mm link. The body link fits into the extractor groove on the cartridge case. The U.S. Navy uses the link with the M63 Stoner Machine Gun. The U.S. Army uses the link with the M249 Machine Gun. Ballistic data for 5.56mm ammunition. Model Cartridge Weight Cartridge Length Propellant Projectile Weight Chamber Pressure Velocity 15 ft (4.6 m) from muzzle M193 Ball 182 gr (11.79 g) 2.26 in (57.4 mm) WC 844 or CMR 170 56 gr (3.63 g) 52,000 psi (3,656 kg/cmÂ²) 3,250 fps (991 mps) M195 Grenade 126 gr (8.16 g) 1.9 in (48.3 mm) IMR 4475 N/A N/A 140 to 165 fps (43 to 50 mps) * M196 Tracer 177 gr (11.47 g) 2.26 in (57.4 mm) WC 844, IMR 8208M, or CMR 170 54 gr (3.5 g) 52,000 psi (3,656 kg/cmÂ²) 3,200 fps (975 mps) M197 HPT 174 gr (11.27 g) 2.26 in (57.4 mm) SR 7641 56 gr (3.63 g) 70,000 psi (4,921 kg/cmÂ²) N/A M199 Dummy 150 gr (9.72 g) 2.26 in (57.4 mm) N/A N/A N/A N/A M200 Blank 107 gr (6.93 g) 1.9 in (48.3 mm) HPC 13 N/A N/A N/A M232 Dummy 161 gr (10.43 g) 2.26 in (57.4 mm) N/A N/A N/A N/A M755 Blank 112 gr (7.26 g) 1.9 in (48.3 mm) Hi Skor 700X N/A N/A 172 to 198 fps (52 to 60 mps) ** M855 Ball 190 gr (12.31 g) 2.26 in (57.4 mm) WC 844 62 gr (4.02 g) 55,000 psi (3,867 kg/cmÂ²) 3,025 fps (922 mps) *** M856 Tracer 191 gr (12.38 g) 2.26 in (57.4 mm) WC 844 63.7 gr (4.13 g) 55,000 psi (3,867 kg/cmÂ²) 2,870 fps (875 mps) *** M862 SRTA 108 gr (7 g) 2.03 in (51.56 mm) WPR 260 3.6 gr (0.23 g) 15,750 psi (1,107 kg/cmÂ²) 4,525 fps (1,379 mps) M995 AP 180 gr (11.66 g) 2.25 in (57.15 mm) WCR845 52 gr (3.37 g) 50,250 psi (3,533 kg/cmÂ²) 3,324 fps (1,013 mps) *** *M195 - Velocity at 5.5 ft (1.7 m) from muzzle for projected grenade. **M755 - Velocity for projected M743 Sting Ring Airfoil Munition. ***M855, M856, M995 - Velocity at 78 ft (24 m) from muzzle. Cartridge, 5.56mm, Ball, M193 The cartridge is used by the M16 and M16A1 rifles. The cartridge is intended for use against personnel and unarmored targets. This item is a training standard item used in both training and combat. This cartridge can be fired by the M249 machine gun, but accuracy is degraded; therefore, it should only be used in emergency situations. The M193 cartridge has a bullet with a copper alloy jacket and a lead antimony alloy core. The cartridge is identified by a plain bullet tip. Type Classification: STD - AMCTC 5143. Type Classification Date: 1975. Unit cost: $0.24 (Fiscal Year 2005). Cartridge, 5.56mm, Grenade, M195 The cartridge is used by the M16 and M16A1 rifles. The cartridge provides pressure, on functioning, to project grenades to a desired target using a grenade projection adapter. The cartridge is identified by a rose-petal (rosette-crimp) closure of the cartridge case mouth sealed with red lacquer. Type Classification: STD - AMCTC 6919 Cartridge, 5.56mm, Tracer, M196 The cartridge is used by the M16 and M16A1 rifles. The tracer is intended to permit visible observation of the bullet's in-flight path or trajectory to the point of impact. Its main uses are for observation of fire, incendiary effect, and signaling. This cartridge can be fired by the M249 machine gun, but accuracy is degraded; therefore, it should only be used in emergency situations. R284 tracer. The cartridge is identified by a red bullet tip. Type Classification: STD - AMCTC 5055 Cartridge, 5.56mm, High Presure Test, M197 The cartridge is used by the M16 and M16A1 rifles. The cartridge is used to proof test weapons during manufacture, test, or repair. The cartridge is loaded with a special propellant to produce pressures substantially in excess of the service round. The cartridge is identified by a stannic-stained (silvered) or nickel-plated cartridge case. Type Classification: STD - AMCTC 4484 Cartridge, 5.56mm, Dummy, M199 The cartridge is used by the M249 machine gun and M16/A1/A2/A3/A4 and M4-series weapons. The cartridge is used for practice in loading 5.56mm weapons, for simulated firing to detect flinching of personnel when firing, and for inspecting and testing the weapon mechanisms. This round contains no propellant. The cartridge is identified by six longitudinal corrugations (flutings) in the cartridge case and by the absence of a primer. The primer well is open to prevent damage to the firing pin. d. Type Classification: STD - AMCTC 4662 Cartridge, 5.56mm, Blank, M200 The cartridge is used by the M249 machine gun and all 5.56mm rifles (M16/A1/A2/A3/A4 and M4-series weapons). A blank-firing attachment must be used to fire this ammunition. The cartridge is designed for simulated firing in training exercises and for saluting purposes. The M200 blank cartridge has no projectile. This is a training unique item; not used in combat. The original M200 blank cartridge had a white tip. Field use of this cartridge resulted in residue buildup, which caused malfunctions. Only the violet-tipped M200 cartridge should be used. The cartridge is identified by a rose-petal (rosette-crimp) closure of the cartridge case mouth. An engraved knurl is located 1/2 inch from the head of the cartridge case. Type Classification: STD - AMCTC 5942. Type Classification Date: Prior to 1977. Unit cost: $0.09 (Fiscal Year 2005). Cartridge, 5.56mm, Dummy, M232 The cartridge is used by the M16 and M16A1 rifles. The cartridge is an inert round used for testing the mechanisms of 5.56mm weapons. The cartridge is identified by a black chemical finish over the entire round and by the absence of a primer. Type Classification: STD - AMCTC 4485 Unit cost: $0.52 (Fiscal Year 2005). Cartridge, 5.56mm, Blank, M755 The M755 blank cartridge is especially designed for use with the Sting Ring Airfoil Munition System which consists of the M234 launcher and the 64mm riot control M743 projectile fired from the M1GA1 rifle. The cartridge is only for use with the M234 riot control 64mm projectile launcher. The launcher is attached to the flash suppressor of the M16A1 rifle and actuated by firing an M755 5.56mm blank cartridge. The M755 blank cartridge is the only cartridge that will give the projectile M743 the proper velocity. Use of other blank cartridges may damage the system. The blank cartridge is fed into the firing chamber. When fired, the primer ignites the propellant. The expanding propellant, gases pass from the muzzle of the rifle into the launcher manifold. The projectile is ejected from the launcher barrel to a maximum range of 328 feet (100 m). The propellant charge is not sufficient to eject the cartridge case which must be ejected by pulling the charging handle of the rifle all the way back. The cartridge is closed with a seven petal nose crimp and moisture sealed. The crimped tips of the cartridge is painted with yellow lacquer for identification and thus lessen the chance of mixing them with the standard 5.56mm blank cartridges. Type Classification: STD - MSR 04786005 Cartridge, 5.56mm, Ball, M855 The cartridge is used by the M249 machine gun and the M16A2/A3/A4 and M4-series weapons. The cartridge is intended for use against personnel and unarmored targets. This is a training standard item used in both training and combat. The M855 cartridge has a 62-grain, gilded metal-jacketed, lead alloy core bullet with a steel penetrator. The primer and case are waterproof. This ammunition should not be used in the M16A1 except under emergency conditions, and only at targets less than 90 meters in distance. (The twist of the M16A1 rifling is not sufficient to stabilize the longer projectile of the round). The cartridge is identified by a green bullet tip. Type Classification: STD - MSR 05826003. Type Classification Date: 1982. Unit cost: $0.26 (Fiscal Year 2005). Cartridge, 5.56mm, Ball, M855, Lead Free The M855 "lead free" ball cartridge has a bullet with a conical steel insert and a tungsten composite core in a copper alloy jacket. The intended use is to maintain environmentally "clean" ranges. The cartridge is identified by a green bullet tip. Type Classification Date: 1982. Unit cost: $0.38 (Fiscal Year 2005). Cartridge, 5.56mm, Tracer, M856 The cartridge is used by the M249 machine gun and the M16A2/A3/A4 and M4-series weapons. The tracer is intended to permit visible observation of the bullet's in-flight path or trajectory to the point of impact. This is a training standard item used in both training and combat. The M856 tracer cartridge has characteristics similar to the M196 tracer with a slightly longer tracer burnout distance. The M856 is ballistically matched to the M855 ball cartridge. The tracer bullet delivers a visible red light signature through its trajectory. The M856 does not have a steel penetrator. This ammunition should not be used in the M16A1 except under emergency conditions, and only at targets less than 90 meters in distance. (The twist of the M16A1 rifling is not sufficient to stabilize the projectile of the longer ammunition). The cartridge is identified by an orange bullet tip. Type Classification: STD - MSR 05826002. Type Classification Date: 1982. Unit cost: $0.30 (Fiscal Year 2005). Cartridge, 5.56mm, Plastic, Practice, M862 Cartridge, 5.56mm, Short-Range Training Ammunition (SRTA), M862 The cartridge is used by all rifles when equipped with the M2 training bolt. The cartridge is for training in local and urban training areas where range restrictions preclude use of full range standard service ammunition. Although M862 SRTA closely replicates the trajectory and characteristics of service ammunition out to 25 meters, it should not be used to set battle sight zero of weapons to fire service ammunition. The settings that are placed on the sights for SRTA could be different for service ammunition. If adequate range facilities are not available for sustainment training, SRTA can be used for any firing exercise of 25 meters or less. This includes the 25-meter scaled silhouette, 25-meter alternate qualification course, and quick-fire training. SRTA can also be used for Urban Operations training. The cartridge is identified by a blue plastic bullet. Unit cost: $0.61 (Fiscal Year 2005). Cartridge, 5.56mm, Armor Piercing (AP), M995 The cartridge is used by the M249 machine gun and the M16A2/A3/A4 and M4-series weapons. Procurement is intended for use against current and future light armored targets. The M995 offers the capability to defeat these targets at ranges 2 to 3 times that of currently available 5.56mm ammunition. The cartridge consists of a projectile and a propelling charge contained in a brass cartridge case to which the projectile is secured. The projectile consists of a dense metal penetrator (tungsten carbide), which is enclosed by a standard gilding metal jacket. An aluminum cup sits at the rear of the projectile for the purpose of properly locating the penetrator within the projectile. The cartridge utilizes a conventional brass case and double base propellant. A standard rifle cartridge primer is used in the case to initiate the propelling charge. The penetrator is similar to components used in other small caliber cartridges currently used by the US Army, but tungsten has better penetration capabilities than the other materials and is the design feature, which enhances the armor piercing capability of the cartridge. This cartridge is identified by black bullet tip identification paint. Type Classification: Std - 29 Mar 96 Unit cost: $1.44 (Fiscal Year 2005). AMMUNITION EFFECTS The penetration that can be achieved with a 5.56mm round depends on the range to the target and the type of material being fired against. The M16A2/A3/A4, M4, and M249 achieve greater penetration than the older M16A1, but only at longer ranges. At close range, the weapons perform the same. Single 5.56mm rounds are not effective against structural materials (as opposed to partitions) when fired at close range - the closer the range, the less the penetration. The 5.56mm round is affected more by close ranges than the 7.62mm or .50 rounds. ï‚§ 5.56 mm Maximum Penetration. For the 5.56mm round, maximum penetration occurs at 200 meters. At ranges less then 25 meters, penetration is greatly reduced. At 10 meters, penetration by the 5.56mm round is poor due to the tremendous stress placed on this high-speed round, which causes it to yaw upon striking a target. Stress causes the projectile to break up, and the resulting fragments are often too small to penetrate. ï‚§ Reduced Penetration. Even with reduced penetration at short ranges, interior walls made of thin wood paneling, sheetrock, or plaster are no protection against 5.56mm ball ammunition rounds. Common office furniture, such as desks and chairs, cannot stop these rounds, but a layer of books 18 to 24 inches (457 to 610 mm) thick can. ï‚§ Wood and Cinder Blocks. Wooden frame buildings and single cinder block walls offer little protection from 5.56mm rounds. When clearing such structures, soldiers must ensure friendly casualties do not result from rounds passing through walls, floors, or ceilings. ï‚§ Armor-Piercing Rounds. Armor-piercing rounds are slightly more effective than ball ammunition in penetrating urban targets at all ranges. They are more likely to ricochet than ball ammunition when the target presents a high degree of obliquity. The following common barriers in urban areas stop a 5.56mm round fired at less than 50 meters: ï‚§ One thickness of well-packed sandbags. ï‚§ A 2 inch (51 mm) non-reinforced concrete wall. ï‚§ A 55 gallon drum filled with water or sand. ï‚§ A small ammunition can filled with sand. ï‚§ A cinder block filled with sand (block will probably shatter). ï‚§ A plate glass windowpane at a 45Â° angle (glass fragments may be thrown behind the glass). ï‚§ A brick veneer. ï‚§ A car body (round will penetrate but normally not exit). Although most structural materials repel single 5.56mm rounds, continued and concentrated firing can breach some typical urban structures. ï‚§ Breaching Masonry Walls. The best method for breaching a masonry wall is by firing short bursts (three to five rounds) in a U-shaped pattern. The distance from the gunner to the wall should be minimized for best results ranges as close as 25 meters are relatively safe from ricochet. Ballistic eye protection, protective vest, and helmet should be worn. ï‚§ Ball and Armor-Piercing Ammunition. Ball ammunition and armor-piercing rounds produce almost the same results, but armor-piercing rounds are more likely to fly back at the shooter. The 5.56mm round can be used to create either a loophole about 7 inches (178 mm) in diameter or a breach hole large enough for a man to enter. When used against reinforced concrete, 5.56mm rounds cannot cut the reinforcing bars. Structure penetration capabilities of 5.56mm round against typical urban targets (range 25 to 100 meters). TYPE PENETRATION ROUNDS REQUIRED 8 inch (203 mm) reinforced concrete Initial Loophole 35 250 14 inch (356 mm) triple brick Initial Loophole 90 160 12 inch (305 mm) cinder block with single-brick veneer Loophole Breach hole 60 250 9 inch (229 mm) double brick Initial Loophole 70 120 16 inch (406 mm) tree trunk or log wall Initial* 1 to 3 12 inch (305 mm) cinder block filled with sand Loophole 35 24 inch (610 mm) double sandbag wall Initial* 220 3/8 inch (9.5 mm) mild steel door Initial* 1 *Penetration only, no loophole.