Probably the original RG-G feed design was not fully resolved at the time of the drawings.
But after some quick looks my finished assembled feed mechanism, I came up with the following obvious details.
As the rimmed 22 cartridges rotate around the drum with +.120\" of \'single filer\' rib clearance for the feed arm/rims, they stagger/stack on top of each other(rims are only about .040). See pic.
When they get to the feed drum which only has .060\" clearance for the rims, depending where they stacked themselves up they jam up tight. When a bullet tries to feed and it\'s rim is not in line with the rim groove, it don\'t fit. In the pic you can see the staggered/stacked rims(3@.120) trying to fit into the .060 feed drum rim groove.
So I\'m thinking of putting a bevel on the feed drum from the .120 \'single filer\' rib dimension to the .060 feed drum inner dimension.
This will ramp the cartridge rim into postion in the feed drum no matter where it lands on its \'feed drum\' approach, from the single filer groove.
Next is the .120 height of the pins that actuate the feed drum, not quite high enough to catch the feed drum pins. My parkerized pins are like anti-skid and lock up instead of slip nicely into position. I\'m going to wait till i get the bullets to come out of the feed drum properly until this is re-engineered because the spring loaded feed arm may push the feed drum/pins around a little more and catch properly.
Working with the drum magazine door off helps a lot to see what going on(or not!) with the mechanism.