Don't shoot off the hood of your truck. Use the tailgate. I learned my lesson the hard way. Several years ago, I was sighting in a Remington 7400 Carbine shooting from the hood of the truck. It wasn't until I was done shooting that I discovered that the muzzle blasts had flecked the paint. Okay, you can stop laughing now

Get yourself a rest and shoot from the tailgate.
Mr. .45-70