Complex sentence: The American M16 rifle used the M7 bayonet which is based on earlier designs such as the M4, M5, & M6 bayonets, all of which are direct descendants of the M3 Fighting Knife and have spear-point blade with a half sharpened secondary edge.
Split into simpler sentences: The American M16 rifle used the M7 bayonet which is based on earlier designs such as the M4, M5, & M6 bayonets. All of which are direct descendants of the M3 Fighting Knife and have spear-point blade with a half sharpened secondary edge.