other than shooting at the range to make sure my gun eats the ammo i feed it, i personally had not done any expansion/penetration test on the ammo i carry. Today i decided to do a little test. I setup 5 water jugs in a row with a wood board behind them on the off chance of penetration through all five. Test ammo was doubletap 10mm 165gr gold dot, doubletap 200gr controlled exp jhp, and 45acp 230gr+P hornady jhp. The gold dot penetrated thru 3 jugs and dented the back of the 4th jug. The 200gr went thru four jugs and dented the front of the 5th jug. Hornady penetrated thru 3 jugs and rested in the 4th. The biggest difference in the rounds was the "water explosion". The gold dot completely destroyed the 3 jugs it went through. The 45acp just left mediocre holes as it penetrated. Anyway, here are a few pictures of the rounds. Using my sisters point and shoot camera, i cant get the lighting right. Next time i will use my dslr. In the first pic the order is 200gr, 165gr, 230gr.