Staff Writer (Updated: 9/25/2015):
By this time, the American military had shifted its attention away from the 7.62mm cartridge and its corresponding M14 Battle Rifle series to introduce the M16 Assault Rifle chambered for the smaller and lighter 5.56x45mm NATO cartridge. The shift to the new cartridge meant that a single infantryman could now carry more ammunition - though at the expense of reduced penetration at range. The 5.56x45mm cartridge was a NATO standard round which led the Japanese military to follow suit and adopt a new gun chambered for it - this becoming the Howa Type 89 of 1989. Like the Americans, the Japanese abandoned the Battle Rifle concept and accepted the Assault Rifle as a standard frontline weapon system.
Development of the weapon fell to the Japanese Defense Agency with manufacture once again coming from the Howa Machinery Company Ltd who already had experience in producing the Armalite Ar-18, an AR-15/M16-family weapon. The development phase yielded several forms of the rifle that would eventually become the Type 89 in service. Something of a no-frills service rifle, the gun became yet another in a long line of indigenously-designed and produced rifles for the nation of Japan. The finalized form was given a weight of 7.7 pounds and an overall length of 36 inches with the barrel assembly measuring 16.5 inches long. Feeding could be from either a 20- or 30-round detachable box magazine with the rate-of-fire reaching 750 rounds-per-minute. Optimal engagement ranges fell within 500 meters and muzzle velocity listed at 920 meters-per-second.
At its core, the weapon relies on a gas-operated action with a rotating bolt function. The gas arrangement is such that a smoother action results, producing less recoil and stress on critical moving parts when compared to other guns of this class. The firer manages the trigger to achieve single-shot or automatic fire functions as needed though there was a separate mechanism added to actuate the three-round burst mode (leaving the basic shooting function untouched should the burst mode fail in the heat of battle). A bipod is a standard fit under the barrel and the muzzle brake was noticeably slotted. Iron sights allowed for basic ranged fire while the gun was eventually given support for a Weaver and (later) Picatinny rail sections for the mounting of tactical accessories such as optics, aimers and flashlights. An adapter is required to install the American 40mm M203 single-shot grenade launcher under the barrel while the barrel inherently supports firing the local Type 06 Rifle Grenade (introduced in 2006).
The Type 89 Assault Rifle went on to exist in two primary service forms: the original with its solid, fixed plastic stock and the Type 89-F (Type 89 "Para") which features a folding, steel tube stock (collapsing over the left side of the receiver with bracing at the shoulder coming through a simple pad). The "para" descriptor is often used for compact rifle forms as they are generally favored by paratrooper elements. Its issue has also fallen to other specialist troopers such as vehicle crews where a shorter gun length ahs proven ideal for firing from confined spaces.
In practice, the weapon offers basic man-stopping value for JSDF forces in the same vein as the American M16. Quality and finish are considered quite good, particularly when compared to the preceding Type 64 series and the new gun is less complex in terms of operation, repair and maintenance. Despite its general resemblance to the American M16 and its related family of arms, there are slight differences in the Type 89 that include a follower featured on the magazine to hold the bolt open after firing the final cartridge. The well itself is also not tapered or beveled as it is in the M16. Recent JSDF experience in Iraq has brought along several refinements to the line as well: a left-hand selector has been seen as has increased support for tactical accessories. A shortened carbine form, following the general form and function of the American M4 Carbine, has also resulted from recent deployment experience by the Japanese military.
For the near future, the Type 89 will remain the standard frontline service rifle for the JSDF though the service may very well follow other regional powers in adopting a more modern weapon system.