I don't know where Taylor got his "2175 fps" muzzle velocity of the 286 gr bullet from the 9.3x62. The oldest numbers I found in German catalogs were 2230 fps (26" test barrel) and 2270 fps (28" test barrel). The ca. 1930 ICI / Kynoch catalog credited it with 2250 fps. In the 1930s this had increased to 2340 fps, a gain of merely 90 fps. Today, 9.3x62 286 gr factory loads are advertised at: Sellier & Bellot 2280 fps, Norma 2362 fps and PPU 2264 fps.

Rather, Taylor was thinking about the RWS high speed load with the 258 gr H-jacket at 2697 fps. On page 141 of his book he shows a picture of this load:

Due to his inability to handle metric numbers Taylor erred here in several ways. He did not note that the RWS H-jacket was lighter, 258 vs. 286 gr. The velocities he gives for both bullets are way too low. The RWS H-jacketed bullet was sort of a semi-partition. It featured a soft lead core front, separated from a hard one in the rear by a deep fold of the jacket. The front part was intended to expand and break up into shrapnels to increase damage inside soft skinned game, while the rear half did not deform and continued penetration. There were copper capped and plain lead nose versions available in other calibers, but in 9.3 mm it was offered in lead nose form only.