Without the bore sight I do not think you will make that screwup again. Just sight it in at 25 yards to get on paper and then move it out to the range you want to sight it in at. Then you can shoot over the chrony for velocity check. That is if you did not ruin your chrony on that first screw up.
I nicked my chrony once, but the darn thing is still working great.
RELH