Clark recoil spring question

Maybe a question for Jon. In my Clark Heavy Slide I just got, I’m shooting 3.9 BE, 185 gr Zero LSWCHP.
With the stock spring, whatever that is, I had a lot of failure to feeds. I replaced with a 12lb spring, “felt” lighter. 
Still just drools the cases onto my arm, and short cycles a lot. Advice on what I should use spring wise? Also, the bullet nose gets jammed on the feed ramp/barrel if it doesn’t fully feed. Could this be just because of short cycling, or maybe because the bullet nose isn’t compatible with that ramp angle/configuration?
Thanks!

I will private message you on your email

Is that an iron or scoped slide?

Iron slide.