I have an older RS that was inherited to me new in the box. It was probably purchased sometime in the 70's as that's when the Sierra manual that came with it was printed.
Anyhow... I mostly use this press for depriming and resizing duties. It has a slot in the front of the ram where the priming attachment fits. The primer catching tray is a pretty cheesy affair that kinds hugs the base. it usually catches about 1/3 of the spent primers, which usually go flying all over my loading room.
My grand daughter got a drink from the local QT the other day and the kids cup straw was one of those bendy flexible things.
When I saw it I knew I could use it somehow... I envisioned pushing it up into the slot and letting the primers dribble out.
What I found that worked was to cut about a 3" long piece the split away half the length. Now the primers just fall out the bottom into the catch tray. On occasion one will hang inside and fall out on the floor at the bottom of the stroke. ... Still much less than the old way.

I use a long pc of Velcro wrapped around that plastic tray to hole it in place

I had a similar problem with a RCBS JR press. When depriming the old primers would land on the press casting base near ram and sit there until I lowered ram. Then they would fall back into slot and fall out on floor when ram was fully lowered. I place 2 x 7/8"? ID oring around ram and this made the primer fall on into tray. Sure helped stop the dead primer on floor.

I just put the trash can under the press and let 'em fly. Catches them all.

I run a strip of duct down front edge of the press and have 5 gallon bucket under it on the floor. When I am resizing. Catches 90% of them.

Country boy will survive (if he has duct tape)

The trash can underneath I think is the best... I have done that also.

This guy came up with a solution with his 3D Printer. I bought one for one of my old presses for $20 and it works great.

https://www.facebook.com/groups/LoaderTools/

I don't think he has an actual webpage but he responds quickly over Facebook.

A picture so you know what I'm talkin bout