I find this : William P. Jones Gun & Rifle Manufacturer,
25, Whittall Street,
(St.Mary's Square)
Birmingham

"William P. Jones Best 12 Gauge, Manufactured by William P. Jones between 1897 & 1904 (the gunsmith who invented the try gun), this English Best has some features not commonly found on English shotguns i.e. scalloped receiver and side clips; intermingled with classic English design."

could be Jones bought parts of the gun in the Birmingham guntrade were everything was possible in this days.