For as long as I have been following the long snapping position over the last 20 years or so, I cannot recall a snapper changing teams in free agency. Most teams simply retain their existing snapper if they are still performing at high level and its makes economic sense.
This year is no different as veterans Cullen Loeffler (Vikings) and Mike Leach (Cardinals) each signed new contracts for another season with their 2014 teams. Exclusive rights free agent Patrick Scales (Ravens) was tendered a one year contract by Baltimore, while the Ravens did not tender Kevin McDermott, making him a free agent.
With all of the recent snapper signings, there are just six remaining unrestricted free agents. The five are Morgan Cox, Clint Gresham, Tanner Purdum, Thomas Gafford, Jeremy Cain and Danny Aiken.