The 1907 Hunter Arms Chamber Specifications drawing shows the forcing cones as slightly less than 1/2" and a straight taper. The cone angle was shallower in the 1935 drawings with a length of about 5/8".
Austin Hogan stated that, at least early on, the Parker cones were cut at a Ogee rather than a simple taper; this illustration is obviously exaggerated. I've been looking for his posted WT numbers in my files without success.
Was this cone profile continued throughout production?