Browning BLR in .450 Marlin will allow use of pointed bullets like the Barnes X Triple Shock allowing increased range
It is my understanding that barnes does not make that bullet in .458 caliber and that the largest caliber offered in that style is .338. Unless you use a barnes FNX it comes in .458 but it is a flat nose. Also I cant think of any bullet manufacturers that make a pointed bullet in .458 cal everything is flat nose, round nose, and hollow point.