Don't know if it applies here, but according to articles I've read on designs for .22 RF magazines, and why many older designs were never reliable, stated that retention at the forwards portion of the feed lips was a key factor.
Some more reliable .22 mag lips have small nibs or indentations near the front.
Been awhile since I've owned a Ruger autoloader, mine was never particularly accurate so I sold it off long ago. I remember mine as being extremely reliable with the original mag and a 12 round replacement. It would even feed .22 Shorts flawlessly so long as I put only six in the magazine, and tapped the mag to shift the rounds towards the front.
The Rugeris a great design, but just never felt right in my hand, far too bulky for a .22.