its typical of a high lung shot for there to only be blood, for the last half of the death sprint, and I bet there was a lil trail in the field its just way, way harder to see than it is on leaves. most deer will run a lil distance after shot unless you can hit them hard enough to shut all systems down with hydrostatic shock, or break down the CNS (spine, neck, brain) I've killed 4 deer this fall the distances were 375, 450, 475, and 584. one ran 150 yds, one ran 40, the other 2 DRT. I was shooting a nosler accubond, but at 308 velocities I wouldn't hesitate using a BT.
RR