Yeah, that was my post on that thread. I'm with you, boss. I wonder the same thing.

Taylor mentioned that the .350 No. 2 was actually slightly hotter than the .350 rimless, although one wonders how he could have known that. A fellow who posts here, Vigillinus, had a best Rigby SLE .350 No. 2 and wrote an article about it for Double Gun Journal a while back. He had some of Rigby's old ammo for it (you know the stuff - loaded for the gunmakers by Kynoch) and said that it chronographed 2660+ if I remember correctly.

Yeah, if 2600+ is right (and it sounds like it is) you would think the pressure would have to be over 17.5. Strange, apparently, the British proof houses did not believe that .350 No. 2 pressures were any higher than .400/.350 pressures. As I'm sure you're aware, as a general rule, the British Proofmasters use the peak pressure of the heaviest bullet used in the normal load as the benchmark for developing the proof load which must produce 130% of the benchmark. Presumably, the assumption is that the heaviest bullet will produce the highest pressure. As stated, the .400/.350 and .350 No. 2 cases are, indeed, identical (factory Kynoch .350 No. 2 ammo often had ".400/.350" headstamps). In fact, they are the same cartridge - the .350 No. 2 is simply a light bullet, high velocity loading of the .400/.350 - and the British proof houses treated them as such. So, original British .350 No. 2 rifles were proofed for the normal powder charge used for the heaviest bullet that was used in the cartridge - 43 Cordite, 310 MAX - the .400/.350 load, NOT the .350 No. 2 load, and original .350 No. 2 rifles are so marked. Vig mentioned in his article that his rifle had the 43 Cordite, 310 MAX proof marks. Another DGJ contributor, in an article about a safari in Namibia, mentioned that his Gibbs 350 No. 2 was so marked, as was another .350 No. 2 advertised for sale by Lewis Drake in DGJ. I've handled a number of .350 No. 2s personally and have always paid special attention to them, because I want one and am curious. I've never seen one that was marked otherwise.
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