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In the 1970s when the French Army was looking for a new rifle 5.56mm, they tested a number of foreign rifles alongside development the FAMAS at St Etienne. These included the HK33, the M16, and the FN CAL - and today we are looking at the FN CAL. It already had a four-position selector switch (safe/semi/full/burst), fulfilling one of the French Army requirements. But it did not have sufficient grenade launching capability, and so several examples were modified for trials with unique rifle grenade launching hardware.

Ultimately the HK33 was the best performing rifle, but it was not seen as a politically acceptable option and the FAMAS was chosen instead. I have not seen the trials reports to understand specifically why the FN CAL was unsuccessful, but we know that it was unsuccessful in many other trials, and FN dropped it for the distinct FNC design instead before long.

HK33F Video: https://forgottenweapons.vhx.tv/videos/hk33f-4k

Many thanks to the IRCGN (Institut de Recherche Criminelle de la Gendarmerie Nationale) for allowing me access to film these trials prototypes for you!