I'm planning on buying some reloading dies for it so I can afford to shoot it more.
Yeah, my buddy tells me his is plenty accurate too! I just spoke with him yesterday.
He's reloading for his also. Following is a link for some reload data. Good luck.
Link:
http://www.hodgdon.com/index.php
Link to 450Marlin data:
http://www.hodgdon.com/data/rifle/450marln.php#top