Way too much trouble for an inferior product. Drawn brass is considerably stronger than something off the lathe. There was a spate of articles in the late 80's or early 90's that brought this to my attention including an article in one of the gun magazines which documented case failures of close to 100% in the first firing. And no, I can't recall which magazine/magazines or which company made the product.
Apart from the functional issues of turned brass- do you KNOW what the specifications are for a primer pocket? This to include diameter, depth and radii AND the related tolerances? What about the diameter, depth and radii and wall thickness of the interior? And let's suppose you find and understand the specifications on every dimension for your straight walled handgun round, how will you QC your product? Will you inspect every dimension of every case? Ask any lathe guy out there- onesy twosey's are reasonably easy but what happens when you make thousands? Ask the lathe guys what their scrap rate is and how bad product was found. Are you prepared to indicate every piece of brass when you do the second side? Else your primer pocket could be off center and out of square to the bullet end. What about the metalurgic properties? Are you prepared to properly, no guessing now, anneal your cases? And to top it all off, you have to make each one as perfectly as possible. Your fatigue or daydreaming about Sue and her .......?
are no excuse. What will you use as materials? Say you go with free machining brass. Your chips would weigh well more than your finished product. And be useless. At what cost? Your money would be far better spent on acquiring cartridge cases now. And should you decide to make something plain jane as a 30-06 case, the questions on specifications start taking on an even more ominous tone. Do you really want 50,000 psi going off a few inches from your eyes when you don't KNOW everything there is to know about making cartridge brass?