My department had them in each locker room in the 1970's and 1980's. We used Hoppes #9 in a heated vibra-sonic cleaner. I removed the stocks from my model 14 and hung the gun in the solvent for 20 min. to 24 hrs. I wiped it down, ran patches through it, loaded and holstered it. This method took lead and copper fouling. That gun took 18 yrs of this and is a great gun today.