You will need to check throat fit, length available in your mag and whether the rifle allows you to cycle longer cartridges. I have read of 450M in BLR’s being throated and using unblocked mags or WSM mags to achieve 2.8”
OAL.
A 350Gr TSX is a fairly long bullet but if you are able to load to a 2.8” OAL and the bullet fits the throat, you should achieve quite decent ballistics. Another option is to consider using the 300gr TTSX designed for the 458 Socom.
