I have a Norma on a Rem 700 and a 98 Mauser. While the lock time is a little slow on the Springfield, I don't think it will effect hunting accuracy. My 700 shoots 250gr Spire pts into .7" with 4350 or 4230. I have yet to fire the Mauser. I built that one before I sold my reamer - just in case I needed 2 crazy.
I think 18" would be too short for the Norma or Whelen. If your hunting black bear or moose in dense cover, it might just be the ticket. Elk at 400 yds, I would say put a new/longer barrel on it.
I have some out of production Barnes original bullets in 280gr and 300. I also have an adequate supply of Norma 300gr RN bullets. I haven't shot any of the 300gr bullets yet and don't know if they will stabilize in a 16" twist. The 700 has a 16" twist the Mauser a 14" twist.

Some is Good---More is Better----Too Much is Just Right