Many of you will remember back when the MSBS first appeared at trade shows it was available in both the traditional rifle configuration and as a bullpup. While the MSBS-5.56 has been adopted by the Polish armed forces and has seen continued development, the bullpup variant appeared to have fallen by the wayside. Well at the International Defence Industry Exhibition MSPO 2018 exposition in Kielce, Poland, FB Łucznik Radom have unveiled the latest prototypes of their MSBS bullpup.

According to Frag Out the latest bullpup prototypes have been lightened and improved with the weight reportedly decreasing from 4.05kg (8.93 lbs) to 3.6kg (7.94 lbs) which compares well with the standard rifle’s 3.7 kg (8.2 lb).

Photo showing the earlier MSBS bullpup prototype (top) and the latest prototype seen at MSPO 2018 (bottom) (Frag Out)

According to Frag Out the improved bullpup has an improved monolithic M-LOK forend, the top rail is slightly longer, some re-profiling at the rear of the receiver has removed some weight. The magazine release has been improved with the pressure needed to eject the magazine spread more equally. The same trigger found in the standard rifle is now used in the bullpup model with only two parts needing to be altered.

FB Radom have also redesigned the bolt release lever at the rear of the magazine well, its now in a position more easy to reach. The profile of the lower receiver has also been changed. The rifle still has ambidextrous controls and charging handles and ejection can also be switched from right to left depending on the user. You can find more photos of the MSBS-5.56B on Frag Out’s site.

MilMag’s editor-in-chief also shared some photos of the MSBS bullpup variants on twitter:

Na MSPO Fabryka Broni ujawni rodzinę poprawionych karabinków bezkolbowych Grot: MSBS-5,56B (podst., kbkg, subkbk, kbkm i kbkw) oraz brakujące trzy modele klasyczne MSBS-5,56K (subkbk, kbkm, kbkw ) rozwijane w ramach projektu RAWAT. Część wchodzi w II etap programu zisw Tytan. pic.twitter.com/fmA0spwC7g

— Remigiusz Wilk (@RemigiuszWilk) August 31, 2018

From the photos MilMag have shared it appears that the MSBS-5.56B will come in a variety of barrel lengths and configurations ranging from an ultra short barrelled bullpup PDW to a longer barrelled marksman’s version. The latest 40mm UBGL, which has evolved from the original trigger forward versions, was also displayed.

If your Polish is up to scratch you can check out MilMag’s August online magazine issue which features an indepth piece that looks at the development of the MSBS bullpup design.

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