My stainless stalker was a bit erratic. It seems picky but it can shoot very well. I think it depends on how clean the barrel is- but that is a guess. I have to get more scientific. I know I put some very tight groups using some core-lokt ultras. next time out , same box of ammo - groups were different. Same experience with Gamekings so I am back to the drawing board. I am convinced it is a good shooting gun, just have to figure out my end of it. I even went and bought a Sims De-resonator and will try it on this gun.