This is the sig 556 xI modular rifle . I'm not sure exactly how I feel about modular rifles. Whenever you change a barrel, you have to re-zero the rifle and that seems like a pain in the tail . However, there's something neat about being able to run a Ar-15 magazines and akm magazines in 5.56, 5.45, 300blk and 7.62x39 on the same rifle.
