I have a metal detector which I have used to find hundreds of arrows.
It is not all that unusual for an arrow to go completely under the surface of the ground. In fact, of what I have found I'd guess that 80% are completely buried. I have found arrows fully six inches down in dense sand. I have found arrows that went into the ground at a 45 degree angle and the nock was a couple inches under the surface with a 30 inch arrow. When I shoot my crossbow bolts into a bank of dense sand they almost always go in 20 inches which only leaves 2 inches sticking out. When I shoot a deer the bolts always go through and usually wind up 12 inches minimum into the sand at about a 20 degree angle. 500 grain FMJ bolts with a NAP Spitfire Doublecross on them on the three I have used now have all made it 20-22 inches.
