We were asked to achieve non-destructive entry to a property fitted with this British Standard 5 lever mortise lock. I’d never had to open one of this make/model before. They just aren’t that common around here. Fortunately it’s easy to tell what this lock is by looking in the keyhole. Although branded MHS it is actually manufactured by Avocet.
If you look at the bottom of the faceplate above you will see “BS3621 1980”. The latest version of BS3621 is 2017, which is much more stringent than the 1980 iteration. The most significant difference is length of bolt throw. Modern locks will have the BS kite mark on the faceplate. Other specifications in the BS are resistance to sawing attack, minimum resistance pressure to bolt being forced back in, and minimum number of key differs.
The distinctive cut out of the hardplate and the flared keyway are unique to this lock. Most of the levers have 1 or 2 anti-pick notches.
If you have lost your keys or locked yourself out of your house, locked your keys in your car / boot anywhere in the Forest of Dean, Ross on Wye and surrounding areas give us a call and speak to a locksmith.