My groups are really good, touching at 20 and 30 yards, around a 3 inch group out to 60 yards. I can shoot a group, pull my arrows and shoot again and this time the group is still tight but about 3 inches lower, it bounces back and forth, one time dead on, the next time low. I'm shooting a Bowtech Allegiance, Drop Zone Rest, ACC 371arrows. Is it me or the equipment?