Designed by Arne Brennan, Janne Pohjoispää , and Bill Alexander, the 6.5mm Grendel was designed to have low recoil and high accuracy for the AR-15 rifle. As an improved version of the 6.5mm PPC, the 6.5mm Grendel has proven itself to have an adaptable design and because of that has begun to expand to other platforms like the bolt-action rifle and the Kalashnikov system.