Ok, here are the chrony results for the Gamo 1250 for anyone who is interested.
I don't know all the pellet weights so I will just leave that part out. It is easy enough to find pellet weights if you really need them though. Here goes,
Crosman pointed:1185,1168,1186,1182,1145
Beeman hollow points, the ones with the special coating:1246,1236,1195,1233,1224
German round balls:1102,1094,1090,1065,1121
Beeman Kodiak extra heavy: 996,988,987,1002,990
Logun penetrators:1064,1063,1066,1077,1070
Beeman crow mags:1082,1085,1098,1085,1087
JSB predators:1139,1147,1156,1154,1146
Gamo tomahawks:1192,1182,1186,1170,1195
CPHP's:1186,1185,1181,1185,1191
CP ultra mag:995,995,986,992,978
That's all the ones I tested, I also shot some Raptors just for giggles: 1476,1462,1483, and I shot one RWS R-10 lite, it went 1230.
This rifle is still pretty much brand new and I didn't do any shooting for accuracy but the results clearly show that most of the pellets I tried were supersonic and probably wouldn't do very well anyway. Don't let these numbers sway anybody interested in getting this rifle. Do your research before your purchase and weigh all your options. That's all I have for now, thanks for looking