1. As stated previously the Forster press is designed to allow the die to float and self center in the press and reduce runout.
2. Forster dies are designed with a high mounted expander that has a rubber washer under the spindle lock ring. This also allows the expander to float and self center in the case neck while the neck of the case is held by the neck of the die, and this also greatly reduces neck runout.
Your lockrings are only half the story of the Forster press and the expander and spindle assembly assembly is the other in producing resized cases with the absolute minimum runout.
I'm a cheap bastard and still use my Rockchucker press I bought in 1973 so I bought the Forster expander and spindle units and installed them on my RCBS dies below.
Below a Forster die and its high mounted expander, as you lower the ram the neck of the case is still inside the neck of the die and "CENTERED" when the expander enters the case neck. Meaning no more case necks pulled off center by the expander and greatly reduced neck runout.
Below is cheap bastard trick number two, the RCBS dies have Lee lock rings with its rubber o-ring installed that allow the die to float in my old Rockchucker press.
I hate all of you who have a Forster Co-Ax press, every time I talk about buying a Co--Ax press my finance minister tells me we are going on another cruise and can't afford the Forster Co-Ax press.
Below is my Italian cruise Forster Co-Ax press results but the Italian Pisa dies do not float and self center and it produces extreme case runout.
And two months ago I didn't get a Forster Co-Ax press and all I got on this cruise was a sweating beer mug and a couple hats.
It gets worse, "HER" cat won't even let me sit down in "MY" chair when I reload.
Question: If an American immigrates to Canada and doesn't bring his wife does he get a free Forster Co-Ax press?
Just kidding, I have been married for 40 years to a wonderful lady..............................(who doesn't shoot or reload)