For a revolver you just open the cylinder and look. Next you rod the barrel to make sure there isn’t an obstruction that would be launched by the blank. Shooting for checking in just really stupid.
With an SAA you open the gate, not the cylinder. Secondly, what good is looking at a dummy round loaded in a gun going to tell you? Many look just like live rounds.
And far as testing for dummy rounds by dry-firing, that is standard procedure for many movie armorers.