The BBA M249 Hop Arm from Bristol Based Airsoft is an aluminium hop arm with a concave profile for the VFC M249 GBB, built to tighten groupings at longer range. In BBA's testing, groupings past 40 m improved consistently across several M249s.
BBA tested mainly with .32 g BBs and recommends at least .30 g to get the most out of it. They suggest pairing it with a 4UANTUM GBB bucking.
