Quite a few of the "from Purdey's" crowd suffered unsuccessful (given JP's own "from Manton's") legal action from Purdeys; was it Beesley or Atkin they didn't chase, given that one gave them the self-opening SLE, and the other was JP's first apprentice?
I have seen a damascus barrelled Atkin dated 1918 with the same "from Purdeys" on it.
RG