I really like the 120 noslers as well as the Hornady 120 SSP. You are a lot closer to the 30-30 with the TCU than you are the 223 when it comes to power. I've had extremely good luck seemingly just dumping anything from H110 to 4895 into the case and seating bullets on top...there don't seem to be many bad TCU loads. When my loads don't shoot well, I immediately look at the shoulders of the cases to see if maybe they collapesed a little during loading...that is usually the cause for inaccurate loads in my guns at least. My hunting Barrel is a 12 inch Bellm made barrel and is throated for hunting bullets in the 120-140 range and is aces. My factory 10 inch is also extremely accurate, but really shines with bullets that I consider too heavy for hunting...154s to 162s, though it is accurate enough with the lighter bullets for hunting.
You will probably find the best velocity with something around h335 or 4895. Good luck.
graycg