https://www.gunsinternational.com/g...handling-30-barrels.cfm?gun_id=102243826

Unfortunately the dark image of the barrel flats does not show the additional marks just forward of the flats. Interesting mark by the 'NICKEL' which is probably Jean Falla Nickel Compound Cap

[Linked Image from photos.smugmug.com]

http://www.littlegun.be/arme%20belge/artisans%20identifies%20e%20f/a%20falla%20gb.htm

[Linked Image from photos.smugmug.com]

Should be 1910 to 1921 (no lettre annale)

[Linked Image from photos.smugmug.com]

1905 catalog repro
https://cornellpubs.com/product/114/