With that question, Weapon Blender did us a big service by going ahead and fired a 400fps airsoft rifle to find out what it can break... "We've saved you the trouble of shooting your own fences, cars, walls, houses, ski goggles light bulbs and more by doing that ourselves. Okay, so some of this is pretty obvious (vest). Some might not be (fences?) Tested with a 400 fps Lancer Tactical M4. Tell us what else you want us to shoot."