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The FN PS90 is a semi-automatic carbine variant of the legendary FN P90, intended for civilian shooters for personal protection and sporting use; it was introduced in 2005 and continues to be offered in several configurations.
The FN P90 was developed in the late ’80s by FN Herstal as an attempt to satisfy a request from NATO to replace weapons, mainly handguns and submachine guns, chambered in 9x19mm Parabellum. The round that they came up with was the 5.7x28mm, a bottlenecked round designed to fire a light projectile at high velocities.
The P90 was an overall success, being adopted by numerous Special Operations Forces units and law enforcement agencies that require a PDW (Personal Defense Weapon) including the US Secret Service. This is a PS90, which is essentially a semi-auto P90 with a 16-inch barrel for sale to the US civilian market.
Looking down from the top you can see how the unique magazine lay horizontal across the top of the rifle, allowing a 50 round capacity. The basic FN PS90 version includes a Picatinny rail with rather terrible iron sights integrated with them.
Chambered in the 5.7x28mm cartridge, the FN PS90 utilizes blowback operation and fires from a closed bolt for greater accuracy and reliability. The FN PS90’s civilian legal 16.04″ cold hammer-forged MIL-SPEC barrel is equipped with an integrated muzzle brake to reduce recoil.
Dual magazine latches, cocking handles, and an innovative synthetic thumbhole stock with a molded-in sling attachment point help make the FN PS90 fully ambidextrous. Models with 10 or 30-round polymer detachable magazines are available. Due to the rounds being situated horizontally in the magazine of a rifle, they have to be rotated to line up with the bore of the rifle. This is done with a ramp located at the rear of the magazine.
The PS90 is manufactured in four variants:
- PS90 Standard;
- PS90 SBR;
- PS90 TR;
- PS90 USG
FN PS90 Standard
The PS90 Standard is the current model of the PS90 offered by FN Herstal. It features a MIL-STD-1913 (Picatinny) rail fitted to the top of the receiver, which allows the shooter to mount their preferred optical sight. The rail includes a set of integrated iron sights, as a backup in case the primary sight is damaged. As of 2019, the PS90 Standard is available with a black frame.
FN PS90 SBR
The PS90 SBR variant is functionally identical to the “PS90 Standard”, but instead of the extended 16-inch barrel, this variant retains the standard 10.5-inch barrel of its selective-fire counterpart, thus making it the ballistic equivalent, in semi-automatic only form.
FN PS90 TR
It featured a “Triple Rail” receiver assembly identical to that of the P90 TR. The top of the receiver consisted of a MIL-STD-1913 (Picatinny) rail, allowing the shooter to mount his or her preferred optical sight. Two polymer side rails—one on each side of the receiver—were included for mounting secondary accessories, such as lasers or tactical lights.
FN PS90 USG
In the same fashion as the P90 USG, this model has an aluminum reflex sight housing with a revised reticle. The black reticle consists of a tiny dot inside of a small ring, which is joined by three posts that glow red in low light conditions due to tritium-illumination. The USG reflex sight can be removed and replaced with a special MIL-STD-1913 (Picatinny) rail mount for attaching a different sight, and like other models of the PS90
To disassemble, start by pressing the button located under the magazine and push the upper receiver off of the stock. Next, the bolt and recoil spring assembly can be pulled out of the front of the stock. The PS90 is a straight blowback gun so the bolt has to have a fairly significant mass to operate safely.
There is the extractor at the bottom and ejector at the top of the bolt face. The PS90 ejects downward through the stock of the weapon. There is also a dust cover that can be snapped into place to keep the weapon clean. Next, the buttpad can be pushed up and off the rear of the stock
Finally, you can remove the trigger pack by lifting up on the black lever and pulling the pack out of the rear of the stock. The trigger pack is made almost entirely made out of polymer. There are several generations of PS90 trigger packs, earlier generations included an inoperative auto sear that was removed in the later generations.
Difference: FN P90 vs FN PS90
FN P90 has a shorter barrel and is semi and full auto. FN PS90 has a barrel approx 6 inches long and is only semi-auto. FN PS90 is also available on the civilian market while the FN P90 can only be owned by the military or a law enforcement agency.
Technical specifications: FN PS90
|Manufacturer:||Fabrique Nationale d’Armes de Guerre, Herstal, Belgium|
|Designed:||the late 1980s|
|Type:||Closed bolt, blowback|
|Caliber:||5.7 x 28 mm SS190|
|Barrel:||16 in (406 mm)|
|Weight (empty):||6.28 lbs (2.84 kg)|
|Effective firing range:||250–400 m sight adjustments; maximum firing range: 450 m;|
|Rate of fire:||semi-automatic|
|Magazine capacity:||10, 30 and 50-round magazines|