One thing I never worried about, was the look of Snider to Martini, for the Foundry Gurkhas. Too small to quibble about when looking at 25/28mm figures -- IMHO.

For example, I have a number of the old RAFM Space 1889 'Soldiers of the Queen' British figures, and they are in the 1879 kit - but - armed with Lee-Metford fifles! I always wondered why, and when I had asked Frank Chadwick about that, he said "I liked the look of red coats on Mars for the 1889 period", so that means earlier kit, latter rifled. So, I just painted them up for my 1879 period and ignore the fact that if you really looked close, you can tell the rifle is not a Martini-Henry (again, too small to quibble about IMHO).
But, for those that wants things spot-on, I totally understand. Go to I say!