Talk:The Four Feathers (2002)
This isn't a Mark VI Webley, or any of the Webley-Government series (the Marks I - VI), as it lacks the holster guides which these all had. I found a different shot of it, and I think that's a Pryse-type locking catch behind the cylinder.
I hesitate to say Webley-Pryse, although Webley did use this design of catch (before adopting the more familiar Green-Patent stirrup latch) so did a number of other manufacturers, both in Britain and in Belguim. Auguste Francotte, for example, supplied revolvers to British retailers. (The shot of the broken revolver being loaded gives a good view of both the stirrup catch and the holster guides in front of the cylinder.)
Remington Rolling Block
I know these are already listed, but I think these are also carried by the Egyptian soldiers with the British force, which was also the source for the Dervishes obtaining them (after defeating - completely - an Egyptian army sent against them). It's difficult to get a clear shot, but I think (going by the proportions of the receiver) this looks more like a Remington than a Martini. http://i301.photobucket.com/albums/nn75/IainKD/Film%20Stills/10.jpg
Gatling Gun (... and possible spoilers)
There's a Gatling gun, with Broadwell drum magazine and on a camel saddle mount, briefly glimpsed in the British camp. While this would probably have been in .45" calibre, it chambered a different (and non-interchangeable) round to the .45" Martini-Henry. I don't think it's seen in the battle, either firing or jammed ... in spite of the fact that the Colonel's dead, the square broke and the regiment's blinded by dust and smoke. IKD 03/Mar/2011