These days if I wanted to do accuracy work on one I would look into Accuracy Systems. After that it was a best guess kind of thing. Before the mods it might group the first couple of groups 1.5-3'.
It stays accurate for 20 rounds or so before barrel heat opens the groups a bit. I ended up wth a 1.5 - 2' 3-shot grouping rifle with my handloads or a couple of factory loads. That work was done by myself, Connecticut precision (trigger job) and Great Western Gunsmithing (Gun Doc) who is out of business now.
My first SS Ranch rifle, an early 196 series I had a trigger job done, had it glass bedded, put on a HAR BAR brace, had the barrel shortened and put on a Choate M-14 style flash hider.