vec-tor ... there are no words to describe the joy of someone finally pointing me to the actual solution to this problem that has plagued my Pinbot 30 years from the day I bought it till today, this very moment in time, when someone has actually found and shown me the reason AND the Williams super secret solution which has been sitting in my own book and manual collection for over 27 years...
Some 27 years ago I bought a Jackbot service manual when Jackbot came out so I would have a "modern" listing of Jackbot parts which might be employed to fix or repair my Pinbot sometime in the near future, and that NOW (1995, some 27 years ago) was the time to get replacement parts if they existed. Little did I know they (Williams) had known about this problem in Pinbot and actually changed something in Jackbot to fix it, and that now, at last, I will be able to (hopefully) get mine working reliably for the first time in over 30 years. When I shopped him out and several attempts since then, I tried to get it to work reliably by doing all the things everyone has suggested, and even replaced the spiral ramp three diffent times (I have 3 spiral ramps, 2 original unbroken orange/red ones and a black Jackbot), two different spiral ramp covers, and I don't remember the amount of rubber and post combinations along the right wall I have tried. I adjusted the ramp flaps, the rollback limitter (yes, the original has a little wire that prevented rollbacks into the pops) shooter spring strength, (tried three dfferent ones soft medium and strong), changed the shooter rod assembly twice or three times, plus tried 10 different rubber tips, and centered the shooter on the ball. Yep tried all of that... and still you get "Ring around the collar"
Thank you for a little peace of mind finally. BH