There's only one way to beat true evil, and that's to cheat. Press the following keys together during the game:
Alt+Ctrl+B Enable boxes
Alt+Ctrl+R Toggle rain
Alt+Ctrl+W Toggle wind
Alt+Ctrl+S Toggle snow
You can give this a go: At the firing range press Alt, Ctrl and T. Now fire and a set of co-ordinates appears. Use the cursor keys to adjust the figures so they read 0,0 and your weapon will be targeted.