Charls:

Unknown. We tend to think of certain attributes, such as Metford rifling, hammers, Jones underlevers, etc., as being obsolete by such and such a time. However, I've seen British full nitro hammer double rifles with Jones underlever actions that were built in the late 1930's, so you never know. It does strike me as odd though.

As for loading, Woodleigh makes the bullets. I don't know who makes the brass, but Horneber and Bertram might. If you can't find any, I'm sure cases could be formed from .470 as they share the same parent case. Rim thickness is the same. As I'm sure you're aware, Seyfried's formula for the big nitros is a Federal 215 primer, 119% of the original Cordite charge in Reloder 15 topped with enough dacron polyester fiber to fill the case up so that the dacron is compressed some when the bullet is seated.

Some say that the 119% is a starting load. I don't. In a number of rifles I've used this formula in, 119% would have been over max. I usually start at 110% and work up. Start at 82.5 grains and work up a grain at a time. I would think 3 to 4 grains of fill should be about right, the point is to use enough, not too little. I wouldn't horse it. With a 28" barrel, when you reach 2100 fps, stop.
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