Churchill had his C96 with him at Omdurman. Without rereading his accounts of the charge, I couldn't say if the extra four rounds over a revolver saved his life or not, but possibly so. It would have private purchase rather than issued of course, as I believe officers side-arms all were at that time(?)
He probably had one with him in South Africa too, even though he was there as a journalist. Again, would have to check the literature to verify that. If so, some Boer presumably got it when Churchill was captured with that armoured train.
One has to wonder who was paying for all the hardware of these putative "revolutionaries" who were soon to preside over the murder of tens of millions of Russians?