The 5.56-mm ball M855 cartridge has a gilding, metal-jacketed, lead alloy core bullet with a steel penetrator. The primer and case are waterproof. The ammunition is linked by a disintegrating metallic split-linked belt for firing from the ammunition box.

The SS109 produced in GA used a heavier 4 g (62 gr) bullet with a steel core inserted, fired at a lower muzzle velocity for better long-range performance, specifically to meet a requirement that the bullet be able to penetrate through one side of a steel helmet at 600 meters.

The M193 cartridge is a center-fire cartridge with a 55-grain, gilded metal-jacketed, lead alloy core bullet. The M193 round is the standard cartridge for field use with the M16A1 rifle and has no identifying marks.

As part of its medium and long term plans, the Government Arsenal (GA) aims to supply the requirements of the AFP for 5.56mm M855 (SS109), hence, it embarked on an initial production of 5.56mm M855 in CY 2009 using in-house manufactured cases and primers, and procured bullets. Its existing Loading & Assembly machines for 5.56mm M193 were converted for the purpose, as well as the multi-slide press for the manufacture of links. GA commits to produce higher quantity of this ammunition in the coming years. This is GA's short-term plan to meet the immediate need of the AFP for M249/K3 weapon.

       Eventually, GA aims to acquire an integrated in-house capability by producing also the bullet for M855. Hence, it has programmed the acquisition of a Multi-station Bullet Assembly machine with funds coming from the Armed Forces of the Philippines Modernization Act Trust Fund (AFPMATF) as approved by the Secretary of National Defense in the Program Decision Memorandum for FY 2009 dated May 15, 2008.

       The Bullet Assembly Machine is part of the whole production line for bullet manufacture. Its function/usage is to process and assemble all the bullet components such as jacket, lead core and steel inserts to produce quality bullets. The new machine to be acquired is intended is designed to be convertible also for the production of 5.56mm M193 bullets with a capacity of 125 ppm.

       The acquisition project will establish capability to produce the 5.56mm M855 and enable GA to divert the existing 5.56m M193 1O-Station Manurhin Bullet Assembly, Canneluring and Diameter Sizing machines to 7.62mm ammunition manufacture which would mean reduction in production cost as 12 units of old machines can be eliminated.

       With failure of bidding on 4 December 2009 and 11 March 2010, a negotiated mode of procurement was recommended by the DND BAC to be able to get the most advantageous offer for the government. A Negotiating Team with proper representation from the GA and DND, was created for the purpose as per Memorandum from the SND dated March 28, 2010.