Forming the brass depends on the gun. If you used the AI reamer in a factory .30-30 barrel without setting the barrel back, you are lengthening the chamber by some number of .001". (I don't know the exact measurement off the top of my head.) My -06 had to have the barrel set back almost one full turn to do the proper headspace for the AI improvement. I can fire factory ammo and the -06 and it is headspaced properly, as all
true AI chamberings do.
You can load normal .30-30 loads for the lengthened chamber and if using a squaty 150 grain bullet you might get your brass blown out to some degree, but in my experience it will have a rounded shoulder and will be sooty.
30-30 headspaces on the rim, but you have to consider experience and logic over what someone writes in a book. Not everyone who writes in those books are experts. I have somewhere in the neighborhood of 20 firearms in "wildcat" calibers that require me to make brass. I also have several antique guns where brass is $2-3 each to buy or I can make it from -06, 308 or other parent brass for next to nothing. After making many 1000 brass I am confident in what has worked for me and what hasn't. I appreciate the opportunity to share my knowledge with others. (THANKS,GB!)
I could blow smoke up your a......nose or I can give you good information. My 7x30 waters, 30 Bower Alaskan, 7mm Bower, 7mm Super Mag, 6.5US and 7US all use
rimmed brass. Between these 6 calibers (7 guns total) I have over 3000 rounds of ammo and/or fireformed brass. All have been fireformed with either false shoulders and/or cast bullets loaded to touch the rifling. I have lost very few brass in the process and once fireformed, my brass is ready to trim to length and ready to shoot for group or in competition. I have 7x30 W, 7SM, 6.5US and 7US in pistols that I shoot in silhouette competition out to 200 meters. I have shot the 7US out to 500 meters and hunted with the 7x30 waters. The two Bower barrels were made by Don Bower and both have been shot in friendly 1000 yard competition, however not by me. (I have no place to shoot that far.).
The only real way to learn to form wildcat brass is to do it yourself. You can read from books, look at internet sights, or ask questions in chat rooms like Gray Beard Outdoors. In the end, the only way to get good brass for your gun is to make it yourself or have someone else make it for you. The only way for me to give a definitive answer on how to make AI brass for Dezynco's gun would be by getting more info on the gun, the reamer, who did the reaming, and what reloading dies were purchased to use. Without this additional information, my best suggestion is still to use a mild load of Unique and the RCBS 165 Silhouette cast bullet seated out to touch the rifling to get a good and complete fireform on the brass.
Steve