Greetings
Picture 2's inscription is Al-Khartoum 1318 (Hijra year) while Picture 3's inscription is Omdurman 1318 (same date).
I guess you need to check what year it was exactly but going by the fact that 2005 AD is 1426 Hijra, then a 108 years difference would make it roughly anytime between 1897, 1896 or 1895 (one needs a proper conversion table since a lunar calendar has less days than the gregorian solar one). Mine's just a rough estimate
Is it possible that this baby is a Mahdist sidearm or from a bit later?