Gents:
At this stage, I am living with the front sight as is, but the day will come when I muff a fast running shot in a tight corner, and I will be forced to fit a taller bead.

I haven't seen the Brownells' formula, but its pretty simple triangulation math, many of my past acquisitions have required sight alterations, including a favourite 1903 Mannlicher Schoenauer carbine.

If I may be permitted to 'borrow' this thread for a sec, I am curious as to how many other double rifles, vintage Brit or modern, are sighted-in for the very top of the bead. All my other doubles are sighted for the centre of the bead, which I much prefer, though I recall mention of the former sight-picture on a previous NE thread.
Any comments?