i recently read an article on new cartridge design. it is a slow moving process, because the general gun public likes the basic e 30.06 idea of a design of acartridge. the new wssm's are much better for chamber /bbl life. It is amatter of the burning of the propellant plug, as it moves forward, up the cartridge, then into the throat. the super shorts are much better at this than conventional carts. simple geometry of things like volume space and spacial area tell us this. An even better design would be to have the shoulders of the cart actually ROUNDED, concave like this ( ) but think how much time would have to pass before we accepted this. The problem with the 243 is just what you think it is, too much of the propellant plug goes forward into the throat , and burns up there, like a piece of coal just sitting there. There has allways been a pressure spike problem with the 243, and not so much with other 308 based carts. the 243 just happens to be the worst. The best cart in this class is actually the old 6mm remmy. not that the cart has a much better case design, but the neck does. It is much longer, therefore it allows the plug to burn up before it reaches the throat, also the longer , cooler brass, dissapates heat much better as the plug moves upward, keeping the throat/chamber noticeably degrees cooler. A 6mm throat , even with heavy use , last many times longer than a 243.
