With a brass in station 2 place a credit card between the brass and the arm, the credit card should be touching the brass and the arm and the card shoukd be able to slide up and down freely, that's you're width..
GL..
Fiocchi are great primers, have never had issues with primer not going off in my open and limited blasters. Just finished my case of 12k.. Now on my 2nd.. Going to buy a 3rd over the holidays..