It's not a damaged/broken screw head. It's an engraved pin. Fraser was meticulous – you can see on the pictures above he even gold plated the internals for extra corrosion resistance. There will be a trick to the disassembly that I’m hoping someone knows. I’ve emailed Dickson in Scotland (they own the rights to Dan’l Fraser and still make rifles in the Fraser name) but have had no response.
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