I have begun shooting at extended ranges a short time ago and experienced an unusual happening. Some background to explain, caliber is 6.5x284, 24" barrel 1 in 8 twist, Lapua brass, Lapua Scenar 123 gr., 2975 FPS muzzle velocity, target was at 503 yds. The target was a 2 liter plastic pop bottle filled with water with a 2' by 3' piece of ceiling tile placed 12" behind the bottle. The bullet entered the bottle with a round hole and left with a triangular hole, no explosion of the bottle, only holes front and rear. It then entered the tile at 90 degrees leaving a hole that the bullet will lay in. Any ideas?