Heinz,
thanks for the info on "triple chrome".
I think the "bumper gun" reference was to the many guns post WWII that were plated in
Chroming shops dedicated to renewal of the old steel with chrome plating car bumpers.
These shops popped up everywhere after returning GI's started small businesses and there were many old cars to be repaired or dressed up.
Nothing negative about a bumper gun-
just that it was likely chrome plated in a "Bumper Shop".
JMHO
I searched for and bought my own "chrome" luger - just for this historic connection to the
GI's that brought them back and wanted them to look "special" - and they were plated by
other GI's just making a living.