Poland has ordered 53,000 of the new Polish made MSBS (Modular Small Arms System) 5.56mm assault rifle for its army. This MSBS weapon is an updated version of the 1960s M-16/M-4 design and weighs 3.7 kg (8.2 pound unloaded). As its name indicates it is modular and designed for easy and very reliable operation. MSBS is a short stroke assault rifle that is also available in a shorter 3.4 kg version similar to the American M-4. The MSBS has a standard Picatinny rail for accessories. It can use 60 as well as 30 round magazines. It is also available in a version that fires the AK-47 7.62x39mm ammo. The MSBS is more reliable and flexible than the existing Polish 5.56mm assault rifle and, as its name implies, comes in many (about 11) variations, including several bullpup (magazine behind the trigger) configurations. The army has long wanted this rifle but for until recently the senior commanders were content to use older designs. Since the 1990s Polish troops have been using Polish made 5.56mm assault rifles, most of them the FB Beryl. This is a 3.35 kg (7.4 pounds unloaded) weapon with a 457mm (18 inch) barrel rifle very similar to the American M-16 and many other clones of that design. The Beryl was basically a 5.56mm version of the AK-47 rifle the Poles had been producing for decades. This annoyed a lot of the younger officers and troops.
The MSBS will be competing for export sales with other East European designs. The Czechs have had a lot of success with their CZ-805/806. The CZ-806 BREN 2 was introduced in 2015 as a new version of the CZ-805 BREN which has been used by the Czech army since 2011. The CZ-806 is upgraded version based on combat experience of Czech troops in Afghanistan. The CZ-806 is about 500 g (16 ounces) lighter than the 3.6 kg (7.9 pound) CZ-805. The CZ-086 is a lot easier to use and modular. That is the receiver/barrel assembly can easily be changed so the weapon can fire different rounds or more accurately because of a longer barrel. Moreover the rifle also features quick-change barrels, allowing to change calibers (between 5.56x45 NATO, 7.62x39 AK-47 ammunition) and barrel lengths according to the mission profile like its predecessor. Poland and the Czechs were major producers of Russian designed weapons during the Cold War, including locally designed variants produced for their own troops and export. MSBS designed their assault rifle to compare favorably with the CZ-805 and similar modern designs.