The 24-year-old was previously signed by former manager Gary Middleton during the 2013-14 campaign but only made five appearances – all as a substitute.
On Saturday, after being transferred from North Shields, McGorrigan came off the bench for the last half hour at Ryhope.
He said: “Things look a lot more positive this time round. I didn’t get much of a chance the last time and I feel as if I’ll get more of an opportunity.
“I enjoyed working under Ashington head coach Ian Skinner before whilst manager Steve Harmison was at Bedlington during my time with the Terriers.
“As soon as I heard of Ashington’s interest I knew I wanted to return to the club and had no hesitation in putting pen to paper.”
Skinner said: “Ryan dropped out of the pro game and went to Ashington but didn’t really get a chance.
“I came back into contact with him again at Bedlington where he didn’t really get a chance there either, then he went to North Shields and found some real form.
“He was a regular in the Robins’ side but for whatever reason he hadn’t been in favour over the past few weeks.
“We kept an eye on the situation and think he can do a job for us.
“Ryan came on for half an hour at Ryhope and, bearing in mind he has had tonsillitis all week, showed some good touches, turns of pace and had a couple of efforts at goal.
“He will be a good addition for us.”
The Colliers have also signed Dale Pearson from West Allotment Celtic.