I'll check my Shadow over, but would be good to know a few things:
a) what ammo are you using? brand, weight, reloads? Is it hot loads or competition loads?
b) how many rounds through the gun?
c) what year/batch/ serial sequence is it from?
d) any extremes on the pistol ( like run excessively hot or left out in sub zero temps then fired?)
e) WHERE are these cracks? Pics will help everyone.