SI,
I was going to post this reply on your earlier thread featuring your fantastic Afghan tribesmen converted from plastic Perry ACW Zouaves, but now that you have started a new one dedicated solely to the 9th Lancers in the Second Afghan War, I will post it here instead.
You probably know of Tony Barton, sculptor of AB Napoleonics. You may also know he scratchbuilds amazing 12" Action Figures. A few years ago he built one of a 9th Lancer in Afghanistan.
Here's a couple of pics, which somewhat show the method for slinging the Lance while remaining on horseback...
Here's a LINK to visit the page where these and many other pics of this 12" Lancer are featured, over on the onesixthwarrior forum:
http://www.onesixthwarriors.com/forum/sixth-scale-action-figure-news-reviews-discussion/631852-ninth-lancers-afghanistan-1879-a.htmlYou might also know already that the 9th Lancers took a larger than usual number of uniform variations with them to Afghanistan, which as you will be converting your own Lancers using all plastic figures, and only doing a relatively small number of them, you may be in a good position to take advantage of. For years I've wanted to convert/scratchbuilt a unit of 9th Lancers wearing the quilted cold weather jacket their commanding officer had custom-made for them before they embarked for service in the war. They also wore the long cape in the cold, rain, and snow. In addition to the quilted jacket, they had a more common blue frock, and also a khaki Norfolk type jacket.
Re: service of the 9th Lancers during the war... you can find examples of just about every type of action, from dismounted skirmishing in rough terrain with their carbines, to one or two full-blown charges at the gallop with their lances. But the majority of their service was doing scouting, piquet duties, and providing mounted escorts for key figures such as messengers, important British military or political officers, and Afghan prisoners.
It's very true that much of the terrain in Afghanistan is unfriendly to cavalry, and because of that they spent much of their time serving on foot, but I believe this was always with their horses in the immediate vicinity.
A useful source for your purposes might be the Osprey Men-At-Arms title: "British Cavalry Equipments, 1800-1941," by written and illustrated by Mike Chappell, which happens to feature a colour plate or two of 9th Lancers serving in Afghanistan: