Interesting that he mentions 3 other rifles, a .577, Winchester .25-20, and 6.5 Mannlicher. I wonder where they are?

I suppose the Winchester must have been a Model 92 - did they make the 94 or 64 in that caliber? Could also have been an 1885 single shot or a Model 43 bolt gun, though the latter may be too late for the period. Of course, this assumes he was referring to a .25-20 Winchester rifle and not to the cartridge. If he was speaking of the cartridge, the rifle could have been a Remington 25 pump gun or at least one or two others.