I tried something different last night I used my 550b as a single stage press. If you have the 550 you need to try this it worked great. Anyhow I was sizing some .223 cases and I had the priming system removed . I had to put a 9mm case under the ram so the handle wouldn't fall to far back.
This got me thinking what if there was a primer pocket swagger that would extend up through the primer hole so you could bring the case down after sizing and punch the primer pocket ? In theory it would work perfect but would the shell holder hold it ?

Don't know if the swagger part would work, as the Dillon shellplates have a bit of slop to them, so rolling that crimp out might be a bit less precise than one would want.

In the future, just remove the primer bar return spring and activating rod and tuck the bar back under the primer magazine housing, when going single stage.

It's faster this way.

Chris

The primer tube is still right there in the way. I'm going to try and order the parts to do this.

I've thought about the same thing, I was thinking about using the 1050 punch, then I did some research.  From what I have seen, the 1050 swagger works on the upstroke, not the downstroke and has a pin that goes into the case to support the web of the case during the swagging operation, sort of like the Dillon hand swagger.  I can't see any way of doing this with the 550.