I've been trying to find the write up where a guy, using a Glock 20 shooting a Lehigh Penetrator, performed a penetration test. He had a pane of bullet resistant glass about 3/4" thick, 4 gallon jugs of water and a cinder block wall. He shot the glass...the bullet penetrated the glass, all 4 gallon water jugs and knocked a chunk out of the cinder block wall.
