I have a newish Hunter Elite, stock excepting the GRT trigger, with about 1000 rounds through it. I was at my parent's farm last month, and spent some time with a chronograph and five different types of pellets, weighing 7.9 grams to 8.2 (Gamo, Crossman, and RWS). The low velocity was 861fps and the high was 887fps. RWS Meisterkugeln's @8.2 grams are the gun's favourite, and shoot consistently at around 870 fps. I intend to have this gun tuned, because the twang is utterly ridiculous compared to my 48, and methinks there is real shooting potential there once it is settled down.
So, what sort of velocities are you getting from your Gamo?