I was having a test session today and decided to set a plastic bottle full of water out next to my targets. It was 500ml so it made a 62mm thick by 62mm wide target. The distance was 430mtrs. The 87gr left the barrel at 3200fps. I think then energy at target would be 886Ft/Lbs and 2141fps. The resulting hit was very explosive with the bottle being propelled back about a metre. Later on when I finished my testing I picked the bottle up to find a completely empty copper jacket and pieces of lead like ragged six shot size rattling about in the bottom. The damage to one side looked like a good bursting exit with lots of peppering from the small lead particles. Turn to the opposite side and or any other side and they are unscratched. How can this be? The bullet exploded and came back out the same way? 100% of energy must have transferred to the target but penetration must have been nil?