UNSC Ammunition

While The Royal Allegiance increasingly relied on directed energy weapons such as Particle Cannons for their main weapon types, ballistic weaponry taking the form of bullets, shells and other projectiles still accounted for a not negligable portion of Allegiance weaponry. Particularly during the Swarm War, as many projectile weapons began to be phased out in favour of their energy-based counterparts, ballistic small arms and vehicle weapons remained popular and effective for their stark ability to penetrate The Swarm's natural exoskeleton.

Small Arms Ammunition
Though greatly differing in calibre, these ammunition types provided a wide range in power, range, weight and accuracy, each providing the most imperative characteristics to each weapon, and each role.

4.5x33mm
A miniaturised round designed for armour piercing qualities. While having range and accuracy properties similar to larger calibres, it maintained a much smaller weight and size, allowing for substantially reduced recoil and almost double the ammunition carrying capacity. These qualities made it excellent for use in submachine guns, such as the M8 Submachine Gun, and personal defence weapons, such as the MP8 Personal Defence Weapon System.

6.8x40mm
A small calibre rifle round, the 6.8x40mm was used as a smaller and lighter alternative to larger rifle calibres. While it obviously suffered from decreased stopping power and slightly lower penetration, its accuracy and range were far less affected, and the recoil produced was markedly less than rounds such as the 8.41. This made it an ideal choice for assault rifles such as the M47B Individual Combat Weapon System, and submachine guns like the M19 Submachine Gun.

8.1x45mm
The 8.1x45mm round was an intermediate calibre, high power rifle round used in some assault rifles. More powerful than smaller calibres of the same ammunition type, it also produced more recoil, a result of the bullet’s increased mass and size. It was often complimentary to the 6.8x45mm round, which had slightly less power and recoil. It was considered the ideal balance between a large powerful round and a smaller, lighter one. Several widespread weapons made use of the 8.1x45mm calibre, including the AR20 Individual Combat Weapon System and the M620 Light Machine Gun.

9.22x55mm
An intermediate calibre, high power rifle round used in many battle rifles. While typically producing more recoil than smaller calibres, particularly such as the 4.5x33mm, it benefited from increased stopping power and as a result, better kill efficiency. Used in battle rifles, weapons with larger calibre than assault rifles, it was long ranged and accurate, making it ideal for squad marksman duties and highly accurate mid to mid-long range combat. Weapons such as the BR662-SHR Battle Rifle and BR60 Battle Rifle benefited from this larger round.

12.6x28mm
The 12.6mm round was a large calibre pistol round, used in the J21 Panther. It had good speed, accuracy, range and penetration characteristics, but was a weighty, large round, producing above average recoil.

9.4x33mm
The 9.4x33mm was a standard calibre for most, more conventional pistols. While not as powerful as other pistol rounds, such as the 12.6mm, and not as small as the 4.5mm round, it was a compromise in terms of power, size and stopping power between the two, and was capable of piercing most armour. It was utilised by more conventional pistol designs such as the widely issued M31 Pistol.

Ammunition Types
On top of the many calibres of weapons in the Allegiance arsenal, many different forms of ammunition were available in each calibre, substantially increasing the variability and potency of the Allegiance Armed forces. The following ammunition types were commonly available in small arms calibres:


 * RAPID/RAPID II: The RAPID round was an incendiary armour piercing round with a penetrator of tungsten, cerium and copper carbide (altogether known as TC3). This was designed to provide similar effects of a depleted uranium round, such as self-sharpening, pyrophoric and super dense, but without the side effects associated with a radiological material. The armour piercing nature of the round, coupled with the secondary incendiary effects, made the RAPID round highly effective against armoured targets, though less so against sheilded ones. The RAPID II round improved the weapon's original perfomance and also increased its effectiveness against shields, using an ACE ceramic tip coupled with a secondary TC3 penetrator. The round was coated in an advanced polymer which aquired an electric charge while in flight, aiding in sheild depletion, an effect which was more useful the further the bullet travelled.