It's not supposed to "self load" the next primer, you are to pull the lower portion back against the "upper" that holds the primer tube to load the next primer. When you do that it depresses the small plunger that holds the primers in the tube and it will load a single primer. Once loaded you swing it forward into the "groove" in the ram to center under the down coming shell head and the unprimed case.
If it still doesn't make sense PM me your phone number and we'll talk it through. There isn't anything wrong with the primer feed that I can see and it's not "old" the new ones look exactly the same..
Mr. Boat.....
Your description is exactly how mine has worked since I bought it in the mid 70's. I played around with a LOT of setups and never got to work "AUTOMATICALLY".
I got back, heavily, into reloading as I run about 500 rounds per month through my 9mm's. I got curious. I called RCBS. The lady "Tech Support" and I went over the process. She stated, unequivocally, that when your raised the ram to release the primer arm....that the spring on the arm had enough power or momentum to return to the "home" position and would depress the primer "retainer stop" or the plunger and that a fresh primer would then be released and then would be ready for the next round. You did NOT have to touch the arm or do anything to it. That is why, she said, that RCBS called it AUTOMATIC.
OK...that is when she started sending me parts. With the BRAND NEW components....it still is a Semi-Automatic feeder.
So, your experience is exactly the same as mine....and that is not what RCBS told me.
As I said, I actually got the original Body (it has the pointed plunger where the new one has a cylindrical one), to work at least 90% of the time. However, on the new one....the Allen screw is too short as the spring is longer. So you can not back out the Allen screw enough to release the tension and lock it down with an external nut.
Maybe others will post or chime in.
UPDATE. TWO Amazon reviewers say that you can SOMETIMES get an automatic feed but the primers tend to fly everywhere and they adjust so that they have to push (pull back) the arm for a fresh primer. RCBS does NOT sell this anymore as a kit, but had the replacement components....
ME THINKS the tech support lady is a bit confused....maybe the California air?
Thanks for confirming what I thought....but that is not...unless we had a real "Failure to Communicate" .... RCBS told me....