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With all respect, the fellow on the Gunsmith forum seems to have experience only in forging small parts (probably knife blades) and he says he has no experience in casting.
He is correct on how drop forging is done, but it is not just somebody with a hammer. A drop forge strikes white hot steel with tons of pressure and that is what compresses and aligns the steel fibers to give extra strength. If you want to see a forging, look at the S&W ads in the magazines. That scandium frame is a forging; as you see, it has a long way to go to become a frame. (Actually, aluminum alloy is not strengthened by forging; I suspect S&W just does all their frames the same way.)
Casting, as he says, is simply pouring molten steel into a mold. It is a complex process. First a master part is made (or already exists if the casting is to copy a part) from steel, plastic, or even wood. This is used to make a master steel mold. From the master mold, wax copies of the part are made. Then the wax copies are dipped repeatedly in a ceramic slurry and dried until the wax is surrounded by a ceramic mold. The molten steel is then poured in, which melts out the wax. When the steel cools, the ceramic mold is broken and the part is ready for final machining.
In either case, there will need to be machining. No part from the mold, and even less from the forge, will be "ready to go". How much work needs to be done depends on the part.
Which is stronger? Well, both Ruger and S&W make revolvers in .357 aqnd .44 Magnum. Ruger's frames are cast, S&W's are forged. Which has to be thicker to achieve the necessary strength?
Are 1911 cast frames OK? Yes, for the most part. But the pistol was designed to use forged steel. There is no free lunch, even with modern casting. If a cast part has to be thicker to have the same strength, then cast parts of the same thickness as forged will have less strength. But John Browning designed so much overstrength into the 1911, that it can be made of cast steel and work fine. That is not true of all the parts, unfortunately. (Many people will say that cast parts can be made as hard as forged. True, but hardness is not strength; glass is hard but breaks pretty easily.)
Jim
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