I agree with your hand grenade comments Kid. It is an anti-personel device with a small explsive charge designed throw schrappnel to kill people in the immediate area. The old WWII "pineapple" grenade was segmented to break up and throw little square chunks of steel in all directions while the newer "base ball" types throw "fleshettes", little quarter-moon shaped slivers of steel. They are quite effective at killing groups of people in proximaty of the blast, which, of course, is what they are designed to do. On film not only can they blow up a house they can take out tanks, blow cars and trucks clear off the ground and, of course, there's the inevitable 50 foot ball of flame. My wife once asked me if a hand grenade can make a big fire ball like that and I told her no, but 20 or 30 gallons of jelly-gas will. (Napalm). Hollywierd just loves big fire balls so any time they blow up something they use lots of jelly-gas.