The type 99 rifle was brought about mainly because of the success of the new 7.7mm round. The old type 38 was chambered to fire the standard 6.5mm round and due to the superiority of the 7.7mm when used in conjunction with the new type 92 machine gun, it was decided to convert to the larger calibre. The type 99 fired a 7.7mm rimless round and this along with a semi-rimed and rimmed round which was used for machine guns, must have caused supply problems because of the large amount of 6.5mm rifles still in service. The 6.5mm round was still in production and was never fully replaced. Never the less the type 99 was produced in large numbers and saw action on all fronts.