I so envy you/your '92 in .38WCF!!! Must be a gorgeous firearm! I have been a long-time fan of the .38-40, having owned two of these -- newbees, compared with yours. One was a 1914 manufacture .38 WCF Saddle (757,8xx s/n), and the second was (s/n 966,0xx) which was manufactured in 1926.
With as much respect as may be humanly conveyed
to you, as an owner/hunter of three '92s in this caliber (I never hunted with one of them), in my most humble opinion they are NOT a good choice for most big game in my (North America) area. The cases have proved to be a real challenge for the reloading, with the necked down from .44 WCF case a challenge to size without crinkling, as the brass is quite thin. (I have only "old" brass; perhaps this phenomenon may not exist with new brass)
My mould of choice has been the Lyman 401-43 172 grain mould, using a#43 top punch in my Lyman sizer, with Orange Magic lub.
NOT any sort of ballistician, by any means, I kind of equate the .38WCF with a heavy pistol caliber rifle. You may note that one of the selling virtues of the .38WCF in its "day" was the availability of revolvers chambered in the calibre to complement the rifles/carbines. For loading data, Ruger came out with a "Buckeye Special" revolver with two chambers -- one each in 10mm Auto, and .38WCF. If you Google, and/or inquire Wolfe Publishing re the Handloader Magazine article -- a wealth of bullets and loads is provided therein. If you can access this URL, a good article is printed at
http://docshare01.docshare.tips/file.../243991591.pdf. This is the August 2011 issue #273.
Again, my kudos to you on having this fine firearm; if it were mine, it surely would be cherished as a collector firearm. Doubtful if I'd be carrying a .38-40 in South Africa -- known for its elephants, buffalos, lions, and rhinos! Also -- what would perhaps (cross that and change "perhaps" to definitely!) demand more of my attention are the snakes -- notably your Puff adder and Black Mambas... But.. that's just wussy me.
BEST!!!
geo