I think the good Lt.Col. must simply have been impressed with the Orphans' prowess with their muzzle-loading Enfields.
Seriously, in over 25 years of researching the Orphan Brigade, I have never seen any period record that suggests they ever had revolving rifles, or any sort of breech-loaders. If anyone has found otherwise, I'd sure like to hear about it.
Geoff Walden
co-author, Orphan Brigade Homepage
www.rootsweb.com/~orphanhm/index.htm