Shotgunj, the short answer to your question is, No. But that's why I asked. I'm a pretty casual shotgun reloader, primarily for hunting. I can't see how insulation could matter, but I can accept that a shaped charge may. I thought the taper was merely a design for manufacturing efficiency, as it is with brass cases for rifles and pistols.

I'd be interested to see some apples to apples comparisons of the shaped charge case vs. the straight wall case.

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BrentD, (Professor - just for Stan)

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