It shoots a 260gr 9x39. Still, I’d say the 400m talk is more theoretical than practical. I’m sure you could lob them out and hit a man sized target on a known distance range with a known wind value. At the angle the bullet would be coming down, you could probably hit it behind a wall even. In the wild, that’s a pretty iffy shot.
I’d heard rumors someone was making rifles in that caliber here in the U.S. and trying to get ammo imported as a .300 BLK killer.
ETA: Wolf is making a 9x39 AR upper and importing the ammo.
http://www.thefirearmblog.com/blog/2...205th-arsenal/