They will be reunited with former Scorpions favourite Nathan Mossop as well as former coach Dave Clark, who is a development manager in the area.
Barrow boss Anthony Murray said: “They’ve both done excellently with South Wales.
“These are the type of players we want to be attracting at Barrow – young and with a little bit of experience under their belts. Hopefully they will be good additions for Barrow.”
Scorpions’ chairman Phil Davies said: “We’re disappointed to lose two fantastic players who have given their all for the club, but we know that we can’t stand in their way as they progress up the rugby league ladder. I know both players were disappointed not to make the World Cup squad this year and playing at a higher level will certainly help them progress in their careers.”
Grant was the Scorpions’ top scorer last year with 18 tries in as many games while the Scorpions will be looking for a new captain following Burke’s departure.