It is possible to produce a dummy of a human that replicates fairly closely a real body and this has been done for bullet testing. The problem is that it's expensive and is good for pretty much one shot, maybe, and you still have the problem of a target with built-in variables, which of course is problem that the testing people are trying to overcome to begin with. But for certain limited situations, it has been used. It just wouldn't be practical to use for a large test project for different cartridges.
Shoot low, sheriff. They're riding Shetlands!
Underneath the starry flag, civilize 'em with a Krag,
and return us to our own beloved homes!
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