I couldn’t find a record for him in the WO97 series documents (British Army attestaion & discharge papers) at the National Archives (also available on Findmypast), suggesting he died in service or served in a none regular army capacity.
GRO Death registration
Berry, Frederick Joseph; age 37; Sep Qtr 1905; District Tendring; vol 4a; page 372
Do you have a copy of the death certificate? It may mention if he was still serving at the time.
If not you can obtain one online using the above reference from http://www.gro.gov.uk/gro/content/
If he served in the 2nd Anglo Boer War he should have received the Queen’s South Africa Medal, the roll of which is on Ancestry. I don’t have access to Ancestry’s datasets so cannot look for you and I’m sure someone will have an easier way to get to the rolls, but I can only get to it from:
Search (top menu bar) > All records (scroll down) select United Kingdom (bold type) > (scroll down to Military > select UK, Military Campaign Medal & Award Rolls 1793-1949
Enter his first name (only), last name, keyword sergeant, under campaign or service select South Africa – Second Boer War. If no returns remove sergeant.
You should find him.
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