Sir Charles, I read so much,,,, that i'v read toooo much,so I went back and found this:
Test rifle-win. 1855, single shot #3 barrel 1in 40 twist 40/60,,,i got this confused w/ another articale.
This is the article by mike v.
A Chappie, 1876 w/26" barrel,,bullet sized to.406 smokless powder "NOT FOR USE IN ORIGL. WIN. MODERN REPOS. ONLY.
The article did not give ROT,,, my mistake.