No. Well, you might get away with it but it's not advised. Page 11 of the Ruger manual in the number 2 post tells you.
Firing a .22LR/L/S in a .22 Magnum chamber will result in split cases, no power (bullets are different diameters) and poor accuracy. You can probably get away with it without any major drama, but it's not going to work very well.