C.B Holden has a similar trigger....
Its a Bicycle rifle...that's about all that can be said for it at this point
As to who made it...
There's a proof mark on the barrel which wasn't captured real well by the 4th photo.
it also sez 1610 on the receiver, as well as .22L (.22Long).
I wouldn't try to use .22lr ammo, it might go BOOM.
Not only from too powerful ammo, but the BR's were infamous for being cheaply made with "Alloy Metal",
which, back then, meant the kind of stuff they used in the 60's for diecast Johnny Lightning cars...
chances of metal fatigue...HIGH.
I'd have it checked out by a gunsmith before trying to fire it.
IMHO, clean it with Hoppes #9 & steel wool, make it look pretty, and hang it on the wall in remembrance of your Grandfather.