AGS, your remarks on the efforts of the talented gunsmith who did the rebarrel reminded me of a rifle I have that did a reverse on the Martini connection. Many years ago my very talented gunsmith rebarreled one of my Belgian Comblains with a Martini-Henry carbine barrel that I found in perfect condition. The trick was to remove enough of the 577-450 chamber to allow rechambering for 45-70 while keeping the barrel length above (just!) 16 inches, having a shoulder on the barrel for mounting and timing to the original sights.
