You should take it apart down to every last part and do a thorough cleaning.

The 20 that I have probably had only been "field cleaned" for 40 years. I finally took it apart to every last screw, cleaned the crap out of it, put it all back together and it's now "Smooth Like Butter". I was amazed at how much "gunk" was really in and on that gun in all the inner-working parts.

Unless the metal is twisted, damaged, or missing, a real thorough cleaning will fix that problem.