The Findmypast index of his time in the infantry has a small bio taken from the records which states he was a
storekeeper by trade when he enlisted 30-11-1899 at Pietermaritzburg into the Colonial Scouts at age 22.
The source noted was WO126/30, 63 which is held at National Archives in Kew:
http://discovery.nationalarchives.gov.uk/details/r/C3322681 It is not yet digitized, but perhaps they can do a lookup.
The bio also states that he died at Lourenco Marques in 1903 and his next of kin was his mother, Mrs Snape, residing at Ruabon Road, Wrexham, North Wales.
I am wondering if a mining company was opening up a new area and enticing workers with cheap passage, so regardless of what job they would do, the men were just generically listed as miners if their ticket had been subsidized by the mining company.
There is a minor mention of R. Snape in a diary of another Colonial Scout here:
http://disa.ukzn.ac.za/sites/default/files/pdf_files/thn2264.pdf scroll to image page 15 (which should be page 11 of the actual diary)
This gives no genealogical value but if you read a bit of it, you can "relive" a bit of his life.