As Herb noted, the lands were filed to the same depth grooves, then the grooves deepened with a file to look like the muzzle did originally. That was normal on Jaegers as well. Some of those are filed even further, both lands and grooves, so the muzzle is larger in both dimensions, like the mouth of a trumpet, iirc the Jaeger book's pictures Taylor has.
If a coning took was used, the rifling lands would disappear just inside the muzzle. It doesn't which shows a file was used. It does not take long to file out the lands and grooves if you wanted a muzzle to be PC on either a Hawken or as it seems an English 4 barreled gun.
If I might make a suggestion, highlighting your posts does not do anything for them. We can all read normal text.