This link eludes to the first white contact with the Turkana in 1888 so if we bere that in mind also the vastness in late 19th century Africa and other less celebrated groups of people, this weapon strikes me as a very fundamental response to a new world. There is an 88 mauser that could equally be the inspiration. To me the blunt nose is more indicative of the 1888 model
http://www.everyculture.com/Africa-M...Relations.html