My buddy who shot the Zim buff pictured, was pushing that 400 TSX out of his Rigby with 100 gr. H-4831 at around 2,450 fps or so.
In the .416 Remington, with 75 gr. 4064 and a 400 A-Frame, speed is in the 2,350-2,375 fps range. 78 gr. will push it to 2,400+ (Swift data).
But, I'm sticking with 75 gr for the A-Frame, 77 gr. for the solid, both Swift factory loads.
So with burning that extra powder and with the added gun weight, the Rigby doesn't offer that much over the Remington, A buff will never know the difference. Packing them both for miles in that hot, dry terrain, the hunter will for sure know the difference. As posted before, bud's Zim PH carried a push feed M-70 in .416 Rem. He liked the big RSM, just said it was too heavy. The 400 TSX is the PH's fav bullet for buff. Another Zim buff hunter remarked that his PH was also a 400 TSX advocate. I guess some of those PH's got past alternating softs and solids... I would think there may be some regioal differences in ordinance among PH's.
DF
