I searched the net and get mixed results. So many type of air guns and I'm getting confused. Some shoot plastic bb's, some shoot metal bb's and some shoot pellets. I'm looking for something to plink with and kill critters. I'm not looking for a CO2 powered gun because it is expensive so what is the best one? Some have rifled barrels that shoot both metal bb's and pellets and some just have non-rifled barrels. Then you have different size metal bb's and pellets, WTF?!!! What non-CO2 guns will give me the best FPS? When I was a kid, all I used was my dad's pump bb rifle. I also do not want single shot.