Fishbed is correct.
To my knowledge, the only Ruger that is in service use with any regularity is the Mini 14, which some LE groups use.
They make a ridiculous amount of money in the civilian market, with:
LCP, LC9, SR9c, Mini 14, LCR, SP101, Blackhawk, Vaquero, Mark II, and Mark III all performing well-- among others.
Currently Own: Beretta PX4 9mm, Glock 23 (Gen 4), Glock 19 (Gen 4) x2