RE: energy??
I did a lot of shooting to see what I could shoot though.
The shot gun did very well on cars the 12 gage shot strate though the car door and out the outher door.the 44 and 45 would only shot trough 1 door part time.The 357 and 41 would go though the door every shot but would not go though 2nd door.
The shot gun allso shot WAY in o a v8 ford block.
I have only killed 5 deer with the shot gun every one was full pass though.
All bulets that where used full copper coated.