DrAsus,

Your setup with 100gr of pellets and a 250 SW should be right around 1700fps +/-.

With the Omega scope your aiming points should be close to the following yardages (assuming your around 500 feet of altitude): 100 for the center; 135 for the 150 yard circle; 175 for the 200 yard circle; 195 for the 225 yard circle; and 220 for the 250 yard circle. This should put you within an inch or so at those yardages.

If you sight in dead on at 150 yards your 150 yard scope circle will be on at about 175; the 200, 225 and 250 will be as advertised but you will be close to 4" high at 80 yards so aim an inch or so low for shots between 40 and 130 yards.

I hope this helps.