Jonathan Ferguson pulls another obscure weapon out of our stores, focusing this week on a Colt AR-15 variant sent to the UK for testing by the British Army. Britain was looking to re-equip its infantry squad with a full package of AR-type rifles, with this example with heavier barrell and bi-pod likely taking the place of the squad support weapon or a light machine gun. Jonathan explains why this didn't materialise in the numbers Colt would have hoped.