I have an Umarex Guntlet in .22, I have two air bottles for it. one the stock bottle 13ci and a 21ci. I reduced the regulator pressure in the 13ci bottle to 900 psi. to get less than 20 fpe shooting at 740-730 fps. With H-N 14.66 gr pellets. I shot from 10yrd- 50yrd to get my hold over's. I have to say this gun is shooting dead on all the way to 50yrd. With a SWFA 16x42 quad mill redical. I may not do worth a dang but I'm going to give it a go. Dave