Glad you like the die chapter!
Other aspects of dies and forming cases mentioned elsewhere in the GG books. One is the Hornady Custom Grade dies I got for the .358 Winchester years ago. I was loading the .358 both for me and a friend who didn't handload, partly because .358 factory ammo was getting difficult to find--and then Winchester discontinued the 250-grain load he favored.
I first used a set of RCBS dies, but when .358 brass became difficult to find started necking-up .308 cases. This didn't work all that well with the RCBS die, for same reasons people have stated here. Found out Hornady used a very smooth and elongated expander ball in their Custom Grade dies--which might have been from one of the Hornady folks, perhaps at the SHOT Show. Got a set, and the sizer resulted in pretty darn straight brass with one pass-through of a .308 case.
Have also discussed the COW (Cream-of-Wheat) method of fire-forming--including necks--in at least a couple chapters in
Gun Gack I. One involved forming cases for the .17 Hornady Hornet from .22 Hornet cases after Hornady's version appeared, and the other making 6.5 Creedmoor cases from .22-250s.
The 6.5 CM chapter first appeared in
Handloader in 2010, when more hunters first started to "discover" the round. Some others became interested in buying a 6.5 CM, but were worried that it might fade away and cases would be hard to find.
That didn't happen, of course, but at the time I decided to see how easy it was for form 6.5 cases from widely available .22-250s--since the Creedmoor is essentially the 6.5/.250 Savage Improved. It turned out the easy-button was COW forming, which I did with part of my abundant supply of Winchester .22-250 brass--and the COW cases worked very well.