Dillon 750 shellplate catching on primer

[WSA]

I've loaded about 20K rounds on this press with no problem. 

 

Now the shellplate catches on the primer as it indexes. If there is no primer present, everything indexes perfectly. It's almost as if the primer is a tiny bit high in the primer cup and contacts the shellplate? If you just nudge the shellplate with your thumb it goes into place just fine. 

 

I've taken the primer system apart, played with it, cleaned it, etc. 

 

I'm using Federal Small magnum primers to load 357. Brass is all processed, decapped and sized. Just typing this I realized I should have just tried another primer to see if it does the same thing but I didn't think to do that at the time. But I've loaded abut 3000 rounds with these primers in 357 with no problem. And I've used Federal small and large primers to load 45 ACP as well. Pretty much only do 45 and 357 on this press. 

 

I took apart the primer cup/punch and played around with that as well. I'm sure it's something weird I am missing!