The FN SCAR IAR has been rebranded as the FN Heat Adaptive Modular Rifle (HAMR). This automatic rifle includes the clever IAR feature of firing from a closed bolt (increase accuracy) until it heats up to a certain temperature and transitions to a open bolt configuration (better air flow and cooling).


    From the press release …

    Derived from the innovative FN SCAR™ weapon system, the new FN HAMR is a revolutionary, lightweight, magazine-fed, 5.56x45mm infantry weapon that enhances the automatic rifleman’s maneuverability and displacement speed while still providing the ability to suppress or destroy both area targets and point targets in today’s fluid battle space. In addition, the visual profile and the firing signature of the FN HAMR are virtually identical to that of the standard infantry rifle, thus reducing the counter-fire threat from enemy forces.

    The high-tech FN HAMR platform is a unique, highly adaptable, fully-modular selective fire weapon system that bridges the gap between an individual battle rifle and a squad automatic light machine gun in one compact package. For enhanced accuracy and greater first-round reliability, the magazine-fed FN HAMR initially fires from the closed bolt in either semi-automatic or full-automatic modes. For added safety during sustained fire situations, the FN HAMR automatically transitions into open-bolt operation in both semi-automatic and full-automatic modes before reaching the cook-off temperature of the chambered cartridge. Once the chamber temperature has dropped to a safe level, the FN HAMR automatically transitions back to closed-bolt mode. These transitions between closed-bolt and open-bolt modes are thermally regulated by the FN HAMR and occur without any manual intervention by the operator.


    The rifle weights 11.2 lbs (Including Grip Pod) and has a 650 rpm firing rate. FN claim 1 MOA accuracy when firing from a closed bolt. The company only announced a 5.56mm NATO version (same as IAR).

    Defense Review has also written about the HAMR.

    Steve Johnson

    I founded TFB in 2007 and over 10 years worked tirelessly, with the help of my team, to build it up into the largest gun blog online. I retired as Editor in Chief in 2017. During my decade at TFB I was fortunate to work with the most amazing talented writers and genuinely good people!