I have a new Knight Mountaineer .50 "bare primer" rifle that I am pleased with. I haven't developed a hunting load yet, but am pleased with what I have seen so far. I do wish I had purchaed an Ultralight instead. The Mountaineer is kind of heavy and the flat bottom surface of the stock makes carrying it less comfortable that a rounded bottom. But since I anticipate this being principally a tree stand gun, I think it will be fine. I replaced the stock breech plug with a Lehigh breech plug with replaceable vent liners.

[Linked Image from i.imgur.com]

As far as inlines and the spirit of primitive seasons, if we only use sidelocks then we have to decide how primitive is primitive. My Pedersoli Hawken Hunter has a 1:24 twist, faster than my Knight, and will shoot sabot rounds as well as, or better, than my Traditions Pursuit XL .50 1:24.