The gun, if marked 'Not for Ball' means that it was first proofed between 1875 and 1887 and had some degree of choke. The word choke, which I can see on the barrels in the photo, tend to have been used after 1887 and before 1904 (odd that). It has had a recent re-proof for black powder with the original 2 1/2" chambers (65mm.), and then someone has risked it for nitro proof having had the chamber lengthened to 2 3/4" (70mm.). There will be a date code for when the re-proofing was carried out; this date code is in the lettering and now numbering contained within the little crossed sceptre mark (I can't quite make it out in the photo). The marks used at both British proof houses are now in metric and there appears to be nothing Continental, French, Belgian or otherwise about this gun. If you contact the Birmingham Proof House they should be able to fully explain the marks and to tell you what to look for to see if it is still in proof; I would suspect that it is o.k. as the last two sets of marks are quite recent in type. They should, with the help of the date code and gun serial number, be able to tell you the date it was tested and by whom it was submitted. Lagopus.....
