Have a reply from "The Friedken Group"; holder of the W.J. Jeffery daybooks.
A copy of the record for my Jeffery .256 Mannlicher #21102 (6.5x54) rifle, unfortunately there are no dates noted. I have an email in to see if ledger pages either side might have at least year dates.
What caught my eye was the "Le Personne" did the major part of the work and that of the 8 rifles in the block "Leonard" seems to have been the one to do the "detachable barrel" conversion.
- Mike