I found a reference which I will post when it is uploaded, it shows the bore when marked 16/1 was 0.669 at proof.
I was incorrect when I stated undersized. I was thinking of 12 bores marked 13
That bore diameter provides a reference on barrel wear for you when measure it now
You really need to post a photo of all the barrel flat and barrel stampings in order to get input on shell size and likely pressure guidelines.
Going back to earlier posters a careful evaluation of the gun including all stamps, barrel wall thickness, action on face, style of lockup in order to provide a more competent opinion for type of ammo
Last edited by old colonel; 01/25/17 06:39 PM.