I'm wondering if there comes a point where you would be better off having a gun room rather than paying 1000's on safes. Heavy duty
Security doors are not that expensive, and you may have to pay someone to install it and perhaps secure the windows and possibly ceiling too, but in the end you'll have a substantial place to keep everything. You may still need a separate cabinet inside there for ammo - but those are not expensive and do not need to be that large.
BS7558 which most safes are compliant to is pretty meek to be honest - the test is basically 5 minutes to entry using basic hand tools (not even powered). It is more about unauthorised access than true security IMHO.
Of course, you will need a room for it - or perhaps section one off one within an existing room - but it will certainly be safer than a BS7558 compliant cabinet.
Quick search found this article:
how to builda home office approved gun room
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