As an addition to the above I have read (& fully believe) from loading Co ballisticians the "Max" pressure of any given load can be varied significantly with no change other than crimp. Thus a stronger crimp, being harder to open will produce significantly higher "Max" pressures. "Anyone" who fires a load from a gun & finds the crimp end ripped off & subsequently fires another like load from it totally deserves to have his gun destroyed. When the British were expermenting with the fold crimp shell being loaded in a longer length which would contain a regular roll crimp load & end up approx the same "Loaded" length some 50-60 yrs prior to Bell, the determination was that such was acceptable with no significant change in pressure or ballistics "BUT" that no shell should be fired in a gun in which the "Loaded Length" of the shell entered the cone. It is also to be noted they were only working with "Normal" length cones "Not" a stepped chamber.
