I have some comments, but first I will caveat them:
I am not a student of Berks Co. rifles, so it could be that what I say is wrong for Berks Co.
Behind the Cheekrest:
I like the overall design and flow of it. I think it looks squished up against the rear of the cheek rest. You have a little room to move it aft, and that might balance it better. I can't really tell from the pictures what the design is in the space between the crossing vines. I think it's a leaf? Looks a bit busy to me, but hard to tell from the photo.
The arc leading from the back of the cheek rest to the rear of the comb looks to me like it has a bit of a sharp bend in it, rather than flowing nicely to the top. That may be a Berks Co. thing? I looked at some photos in the library, but it was hard to tell if that is a characteristic of that school. To me, it doesn't flow right.
Forward of the cheek rest:
I think the design is pretty good. The two tendrils that extend forward towards the side panel feel a bit straight to me, maybe they could curve down a bit. Another thought: The design is all tendrils. Could you convert some of the inner ones to acanthus leaves? It might balance it better.
Also, the arc of the molding line you have from the front of the cheek rest to the nose of the comb looks funny to me with that upward hump that then goes back down as it goes forward. I'd rather see a clean arc. Berks Co. thing, or your own design?
Tang:
I think the circular bit right by the tang is too circular. Would it look better if it were more oval or egg shaped?
Overall comments:
A lot of your tendrils seem to have parallel sides. They have a symmetry, rather than growing thicker from base to the volute. Have a look at some of the books on drawing tendrils. Gunsmith of Grenville talks about it. I think you could use the same design, but re-draw the tendrils to be more flowing and dynamic. That would give it a lot better feel. The point is, that I think the overall design is pretty good, but your individual lines need to flow better. Take out the humps and bumps and parallel sides.