Norman,
Has any of the discussion so far been of any interest?
Perhaps your participation could help us learn something from this weapon which has of course interested us.
I agree Jens, the armoury markings would typically be with numbers and as has been noted by Olikara, these characters do not correspond with Indian alphabets he is aware of.
The characters inverted as you have suggested make the circle and three dots reminiscent of a paw print ( much in mind after nature trails here in Arizona
.
Spiral, do you have any examples of this Afghan script? What type weapons does it occur on?
All best regards,
Jim