When did you replace recoil spring or other parts?

[SVTNate]

I'm coming up on 2,000 flawless rounds through my USP9f. When does HK recommend doing more maintenance than just standard cleaning? Where can I buy new recoil springs online, and is it a good idea to replace the c-clip when I replace the spring? What about the smaller, inside spring on the guide rod?

[jasonb]

I don't know if this helps, but I brought my HK USP 9f to my armorer and asked the same question after 5k rounds. He asked me is it works properly. I replied that it did. He told me that it was fine;J