I have the "custom" - homemade stock fitted, the one on the pics. I get 8 shots at 90 ft-lbs after that its starts dropping. I will make and use some havier ammo later to reach even higher energies, Im aiming for 110 ft-lbs(150J) because thats the minimum recuirement for hunting in sweden - Im swedish. The magazine in the Infinity can handle up to 77 grain - 5 gram ammo. I hope I reach 110 ft-lbs before that weight