On another thread mentioned I was not satisfied with the commercial hull conditioning tools for Short 10's To re-shape a plastic hull Heat and proper form is what you want. Tapered aluminum one size fits all did not do a good job for me. Too open at the mouth while not re-shaping the rest of the hull. And most of the tools are too long and hit the primer pocket on short 10's before they do any conditioning.
This is a prototype that's working good for me. Hard Maple chucked up in the wood lathe turned down to a nice fit inside the hull. Taper is enough to get in the fired rolled hull without being so long it contacts the base of the shell. Using it creates a lot more friction than Aluminum tools and works faster. Before and after photos tell the story. These RST's were cut down from fold crimps and have been fired 4 times with no sign of giving up soon.
Few problems, Chucked up in the wood lathe you can run as many as you want one time. Go back later and re-chuck it has some run-out. Not a problem for me I just cut the wood back enough to get round again then go at it. Plan to make some up with Metal center shaft see if they will work in a drill press and maintain center with no run out. No doubt the maple will wear but you can dress it up with some sandpaper if it does.
William