I have a Brattonsound SL5+ with internal ammo safe for sale £185 ovno Hertfordshire/Bedfordshire M1J13/A1
Safe is in generally very good condition with 2x keys (I'd say nearly as new) with minor scuffs associated with transport and fitting etc.
It is 1515mm (H) x 268mm (W) x 271mm (D)* - obviously has mounting holes in the rear
* = as per makers spec I measured 1520x270x270 externally
These are designed for shotguns and low profile rifles but it explicitly states they are not intended for 5 scoped rifles
That said if you had a shtgun or two and up to two stalking rifles that didnt have a pistol grip or a monster sight it would probably be okay!
I would say depending on how you place them you'd probably get more than 5 shotguns top & tailed - maybe 8
This is probably a good mid range safe for someone with 1-2 shotguns and 1-2 rifles to give you a bit of expansion
Typically run about £300 plus delivery new
This is the Level 2 safe with the vault style door - I will post pictures of the actual safe if required as they are too big in MB for this forum but heres the spec and web photo as its exactly like that
https://www.brattonsound.co.uk/sentinel-plus-level2-gunsafe.html
PS - I know not everyone loves Brattonsound with the main complaint being they are smaller than equivalent other manufacturers safe and I agree to an extent (which is why I bought a bigger one) but I had excellent support when I had a lock issue on a different safe