5.7x28 mm@Everything2.com

5.7x28 mm@Everything2.com

Not 100% accurate. See annotated version for more comments.

5.7x28 mm

(thing) by machfive (3.9 d) (print) ? 1 C! Wed May 08 2002 at 3:24:34


Fabrique Nationale was one of two companies (the other being Giat of France) approached in the mid-eighties by NATO planners to solve two distinct problems which arose with military small arms. The first was the ability to arm soldiers whose mission objectives called for the use of both semi-automatic pistols and select-fire assault rifles. The second was the need to combat the increasing proliferation of Level II Kevlar vests and PASGT helmets.
In the past, when a soldier went into a special operations mission, ve often carried an assault rifle utilizing 5.56x45 mm ammunition, and a sidearm which used anything from 9mm to .45 ACP. This was a fine setup, but it required carrying two different kinds of ammunition, and the weight and size of the other ammunition put a limit on how much could be carried. Further, if the primary weapon was a 9mm based submachine gun, such as a Heckler and Koch MP5, they would lose the armor-penetrating ability of the 5.56 NATO rounds.

Fabrique Nationale sought to solve these problems by developing a round which possessed excellent ballistics, small size, and would be equally effective when chambered in a submachine gun or pistol. They answered NATO with the 5.7x28 mm round. It was first demonstrated in 1995 with the FN P90 submachine gun, and later in the Five-seveN pistol.

There are currently three varieties of the 5.7x28 mm round. The raw technical specs of the round are as follows.

SS190 - Standard

Bullet Type - FMJ
Cartridge Length - 40.5 mm
Round Weight - 98 grains
Projectile Weight - 31 grains
Muzzle velocity - 715 m/s for P90, 650 m/s for Five-seveN
Penetration - 48 layers of kevlar at 200 m
L191 - Tracer (color coded red)

Bullet Type - Tracer
Cartridge Length - 40.5 mm
Round Weight - 98 grains
Projectile Weight - 31 grains
Muzzle velocity - 715 m/s for P90, 650 m/s for Five-seveN
SB193 - Subsonic (color coded white)

Bullet Type - FMJ
Cartridge Length - 40.5 mm
Round Weight - 117 grains
Projectile Weight - 55 grains
Muzzle velocity - 320 m/s for P90, 305 m/s for Five-seveN
Penetration - 24 layers of kevlar at 50 m
T194 - Training (color coded green)

Bullet Type - JHP (reducing ammo cost and damage of firing-range backstops)
Cartridge Length - 40.5 mm
Round Weight - 95 grains
Projectile Weight - 28 grains
Muzzle velocity - 705 m/s for P90, 640 m/s for Five-seveN
The technical specs, by themselves, are impressive, but even more so when compared to the rounds which the 5.7x28 mm is designed to replace.


The SS190 ammunition weighs approximately half as much as standard 9mm or 5.56x45 mm ammunition, and has a smaller volume than either. This means you can effectively carry twice as much.
The recoil impulse of the SS190 round is 1/3 that of the 5.56x45 mm and 2/3 that of the 9mm. This translates to one being able to get second and third shots off quicker, or in the case of a full-automatic fire, being able to empty an entire magazine and keep your shots within a 9 inch circle at 50 feet.
The SS190 round transfers nearly all of its energy into its target, minimizing "over-penetration" and reducing the risk of causing negative collateral damage. This is significantly better than the 9 mm, which loses only 30% of its energy in the target, as well as frequent over-penetration.
The SS190 will penetrate a wide variety of body armor, whereas the 9mm will not. It comes close to the level of penetration offered by the 5.56x45 mm round. It will not, however, penetrate materials that the 5.56x45 mm round also cannot, like the 4" ceramic plates which cover the heart in Level III armor.
Due to its low profile and high muzzle velocity, the SS190 offers a nearly flat trajectory up to 200 meters. The L191 tracer round precisely matches the trajectory of the SS190.
Ballistic gelatin tests have shown that the round does not fragment or deform upon impact, instead spiraling and tumbling through soft targets, leaving a tiny .22" hole, and a whole lot of internal deformation. By not fragmenting or deforming, the bullet meets all NATO requirements as prescribed by The Hague Convention.

There are several reasons which explain the rather slow adoption of the 5.7x28 mm round. The first and most obvious, of course, is the fact that it is new. Very few people are willing to take a weapon system into battle if it hasn't been battle tested several times over. The P90 has only been known to have been used once in combat, during the Japanese Embassy crisis in Peru. Unfortunately, details of the weapon's role in that operation did not make it back to the public.

Further, most officers in charge of weapons acquisition for police and military organizations tend to be old school experts who still prefer stopping power and large bore calibers to the "light and fast" designs epitomized by the 5.7x28 mm.

Finally, the design of the P90, for example, is significantly different than the MP5, currently the subgun of choice, and veterans used to the handling characteristics of the MP5 would have a hard time re-training themselves to be as effective.

Although adoption of weapons utilizing the 5.7x28 mm round has been slow, it has been increasing steadily, and looks to continue doing so as battlegrounds begin to change from open air environments to close quarter battle and urban areas and weapons systems designed around it begin seeing more success.

This round is currently unlikely to show popularity for concealed carry or home protection because, despite being ideally suited to the types of threats those situations offer, it is banned in the United States for all but military and police purposes under the Brady Bill due to its armor-piercing abilities.