A 500X of the inclusions; silica, carbon, junk



Burrard was a master, but the second edition was written in 1948, before compression formed hulls, polyethylene wads, the widespread use of reloaded shells, the industrial application of piezoelectric sensors for pressure testing, scanning electron microscopy (SEM), composition analysis by X-ray Photoelectron Spectroscopy (XPS or ESCA), Energy Dispersive X-ray Spectroscopy (EDX or EDS), Ultrafast laser spectroscopy, and likely lots of other stuff I don't understand.
He did mention the industrial use of MPI and radiography dating to the 30s.

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