Rifle is a model 74 Sharps. Load is 68 grains of sifted FFFg Schuetzen (Prefer Goex, but ....). Shoots very well with fire formed cases (no sizing whatsoever) and slip fit boolits that are so sloppy they will fall out if the cases are inverted. For the life of me, I cannot see how these boolits could be concentric. So, bought a Lyman 45 short neck sizing die (the one that serves 45-70, 45-90, and 45-100), hoping to get a little more neck tension. Boolit is 457125 round nose, sized to 0.458".
The plan is to size the necks with the die, then use a BACO .458"/.461" stepped expander plug (mine actually measures .4585") to bring the inside case walls back to about .4575" after the brass springs back.
The die body is threaded to mount the decapping pin, which I do not use, and have removed. Those threads accept the BACO expander plug. But that is a coincidence, right? This die just reduces the neck diameter, it doesn't also expand, right? Or: Is it possible, in a second step, to install the BACO expander in the Lyman neck sizing die body and insert the sized case again, to be expanded? Surely not.
I have an old RCBS die (part of a three die set) I have used in the past to expand these cases, before the rifle told me it liked the slip fits better. I should switch to it for the expansion part of things, right?
Thanks in advance for any information you could provide. I always seem to get the answers I need here.
Chuck