I have the harbor freight US cleaner and it works just fine. Have had it for quite a few years. I also pre heat the water a bit. This way the time it would take the US cleaner to warm up is done.
You might have a cleaning solution problem.
Long Time follower, signed up some years ago and cant remember the log in for my account. This is my new one. Might as well say hello again. haha
Own quite a variation of firearms... Custom builds, store bought and so on.
Regards,
Aaron-