Well, I finally got a chance to shoot my Prohunter with the 45-70 Katahdin barrel. The trigger had previously been reworked and lightened. It breaks cleanly @ 2.5lbs. I mounted a Nikon red-dot sight on it for an upcoming bear hunt and loaded some Hornady 300gr HP bullets to get started. The bullets were loaded with RE7, H335, or H4198, all of which shot at about 2,000-2,500 ft/sec. All testing was done @ 100 yds.
The rifle was much more pleasant to shoot than its bark would suggest. However, I was rather disappointed in the accuracy. Groups with all powders ran 3" to 4.5". While I was not expecting 1 moa groups, I was expecting 2"-2.5" groups with at least one of the powders.
What would you guys suggest to try to shrink the group size? Different bullets? Shimming the forearm? Hinge pin? Other?