Mechanism of target: All we want from a target (actualy, the back stop) is to provide sufficient interference withthe arrow's flight for no less than, say, 5".

Penetration itself is not required. Only the interference.

Why is that distinction important? because I found I can use a bag full of LOOSE old clothes as a target, and the arrow (BH) wont penetrate at all. The cloth is light and looseenough that it moves with the arrow for about 10", depleting all it's energy.

On rear occasions that it did penetrate (probably dense clothes), I reached in from the top of the bag, and unscrewed the BH. field point is an easy pull out.

I guess hanging clothes will do the trick even better. But didnt try it yet.