It is a conventional 12-bore shotgun, in which the lock work is exposed and the breech ends of the barrels have been ground away to expose the chambers.
The gun cannot, of course, be loaded or fired, and it would be useful to hold it as an ?off-ticket? deactivated firearm. Would this be possible?
Deactivation standards are very precise, and only those guns that conform exactly to them are eligible to be approved as deactivated and receive the requisite proof mark and deactivation certificate.
As I understand it, in this inert demonstration gun, the action has been cut away so that the internal workings and, crucially, the chambers are also exposed.
This would mean that the chambers could not be blocked or plugged as the deactivation standards require.
For deactivation, the striker noses would also need to be ground away, and this would certainly affect the gun?s demonstration value.
If you want to pursue deactivation as an option, then consult one of the two proof houses, which will be able to advise.
Alternatively, have the gun added to your certificate and accept that it will have the same legal status as a working shotgun and will remain subject to the usual security conditions.