Brent: previous thread about lengthening cones to mitigate the rise in pressure with using long for chamber shells
https://www.doublegunshop.com/forums/ubbthreads.php?ubb=showflat&Number=621506

Bell's study did suggest that cone lengthening will indeed decrease the pressure rise.

Although removing metal obviously does not make a barrel stronger, because angle of the cones is sharper than the external taper of the barrels, cones can be lengthened BY AN EXPERT and the resultant wall thickness is about the same as the end of chamber wall thickness.

[Linked Image from photos.smugmug.com]

Up until the magic of long cones marketing started, the standard was 3/4 - 1" but some European makers used even shorter cones.

[Linked Image from photos.smugmug.com]

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