The 23-year-old prop joined hometown club Tigers’ academy from Oulton and had spells with Dewsbury and on loan at Coventry Bears before signing for Hunslet ahead of the 2020 season.
After that campaign was cut short by Covid, he left Yorkshire to join the armed forces and is currently stationed in Cornwall.
“After what’s been going on over the past couple of years and having time out of the game at a professional level, I will try and pick up where I left off to help this team,” Ray said.
“I thought when Covid hit my rugby league days were over by moving down to Cornwall, but when a club like this opens up 20 minutes from where I’m staying, it is a massive opportunity and too good to miss.
“I will be going out there and giving it everything."
Ray added: “It is a brand-new challenge and everything starting off from the ground up is completely different to anything I’ve done before.
“It is good being out of the heartlands because we are a new package and no one will know what to expect from us.
“Hopefully we will shock a few people by starting the season strong and finishing strong.”
Cornwall coach Neil Kelly - a former Dewsbury team boss - said: “It was a no-brainer to sign Jack.
“He is a player that has been raised in the rugby league heartlands, he came through a very good academy set-up at Castleford and has also gained experience playing in the Championship and League One.
“When I found out he was now based in Cornwall, it made perfect sense for Jack to join us.
“We can help him get his career started again and his experience, by being able to play anywhere in the pack, will be invaluable during the season.”