Um, I guess you could use metal for the fletching (feathers) as well. The purpose of fletching is to make the arrow stay the course the feathers act much like the tail of a plane, not doing much except keeping the plane going in a straight line. http://en.wikipedia.org/wiki/Fletching Gives more information. And semi-solid structure that will retain its shape while the arrow is in flight will act like a stabilizer. No matter the weight of the arrow. All they will do is keep the arrow on course and keep it from going end over end. If you are planning on using this beast, I should point out that part of archery is being able to hold your bow steady and 'easily' pull back the string, building up more tension as the string is pulled further back. Thin bow limbs, thin string work better than thick ones in order to get a lot of pent up energy to propels the arrow. It is the speed of the arrow, not so much its mass that determines if it penetrates or not. Plain Metal may not have the springiness you need in order to actually get the spring to launch your much heavier arrow a good distance. Steel fatigues over time and will lose not only its shape but its ability to 'spring back' in order to compensate you will need a metal that has spring potential. You will need a silicon steel or spring steel, not one of the stiffer carbon steels. Arrows are made out of wood because wood is light, lighter ones are made from carbon/carbon composites and/or fiberglass and get further distance because they are lighter than wood arrows. not only do they get further distance they get more initial velocity. It is the speed at which the arrow moves, not is mass, that determines the damage it does. Same thing applies to bullet slugs. If I was to hand throw a bullet slug at you it would bounce harmlessly off of you. however if I load it in a gun and give it the greater energy of gun powder, that same slug can do some serious damage. Bows have different performances, however not just any wood is used, a hard wood with a good spring to it is used for say a long bow. Again some concern is for the lightness of the bow, one has to be able to heft it, hold it out in front of you with your arm extended and be able to hold it steady while aiming. Its easier to hold up 5 pounds than it is 10, 15 or more pounds in this manner. Compound bows with pulleys and laminated limbs redouble the energy bound up with those extra parts. Laminate bows get more energy and longer life because strips of material laminated back to back ends up being stronger and more resistant to being pulled back, ergo more energy is stored as one pulls further back on the string. While a composite bow can get you the spring of metal, this is a bit more tricky to make than a simple long bow. When steel has been used in a bow, it has often been a composite of steel and other materials, getting the extra strength of the steel while using lighter materials for grip and other parts in order to reduce the weight back down. I read some time ago about the Ancient Indians (Of India) experimenting with steel for bows. Two schools of thought were that these were composite type bows or laminate type bows where steel 'straps' were knitted together to make the limbs of the bows. No one has ever tried to make a full metal bow, least ways not one that worked successfully enough to enter the history books.