Guns in "public"

[RobF]

I’m familiar with the need to carry an unloaded gun in a slip when in public...

There's nothing in law to support this.

However there are laws about having an air rifle in a public place without a good reason (or being under age).

So having it un-slipped walking down the road may undermine the idea that you have a good reason to be there. Conversely having it unslipped as you walk across a public footpath may not.