Considering the m46A's were chambered for the 8x57, 6.5x55 and 9.3x57, there is no reason they would not handle your load of 350gr.cast FN bullet at 2,000fps and 52,000psi.

That is still 3,000psi under the 6.5x55 and 5,000psi under the 8x57 and 9.3x62 factory rounds.

Then there are the M46's/M96's chambered for .30/06, which is a 60,000psi round.

As factory loaded by Norma, with a 286gr. at 2,050fps, it is rather anemic. However, that load develops something like 34,000cup and 40,000psi, which is quite beneath that round's capability.

I ran jacketed 300gr. Hornady's (Coreloct and Interbond) sized down to fit, at 2,170fps, just about duplicating 9.3x62's original 286gr. load for speed.