If you're brave enough to disassemble it, a little fine stoning works wonders.
Also, buy 2 extra trigger return springs. on one cut a quarter coil off it at a time and test until the trigger no longer resets after firing.
cut the second spring 1/4 or 1/2 coil above that so it is as light as possible and resets every time.
Remember, on the ruger autos (including the 10/22) part of the trigger pull is compressing the return spring.