I came across a mention that Walter Groff was a close associate of Ed McGivern. I have no information about Groff. Ed Groff who may or may not be related gave my father a 1937 outdoorsman 22 with a custom after market 4 in barrel and a VERY smooth double action. This gun had been reworked for performance. This was given to my father by Ed Groff who was a neighbor in Livingston Montana. My grandfather knew Ed McGivern back in the day in Lewistown MT. Maybe no connections but very intriguing.