The Whisper family of firearm cartridges was developed by J.D. Jones of a company founded in what year?
Whisper (cartridge family): The Whisper family of firearm cartridges is a group of wildcat cartridges developed in the early 1990s by J.D. Jones of SSK Industries. SSK Industries: SSK Industries, Inc. is an American designer and manufacture of guns and accessories. SSK Industries:  Founded in 1977, the company is known for its custom Contender and Encore barrels.
1977