Took the Knight Mountaineer .45 out today and also my Hawken with Hoyt 1:20 twist barrel .45 cal. I got the knight zeroed in for hunting this year. Going to be working on getting it shooting smaller groups but I can't argue with 3 shots at right about 1" maybe a tad over. The Hawken shot fairly well too but also needs some more playing with. I wouldn't hesitate to take either out for deer or bear the way they are right now.
Thanks to Sabotloader for sending me some shims for the BP and as you can see when compared with an unfired primer I had absolutely zero blowback.
Also my primers were for the most part dropping out of the Lehigh bare primer adapter.

Just a quick note. If you compare the top and bottom targets you'll notice the bottom target has a bullet hole just a bit over 2" left of the bull. This was with 80 gr of Black MZ that I had close to sighted in on an earlier trip and had 3 in my butt stock holder ready for hunting. Like a dummy Ieft my preloaded tubes of Black MZ on my bench at the house and had to use the Swiss 1 1/2. So I sighted in with that. You can see that the 80 gr load of Swiss hit about 2" right. After moving over left and down and firing the 5th shot I decided to shoot one of the 3 Black MZ preloads I had and that was the result.
Funny how the two 80 gr loads of Black MZ and Swiss 1 1/2 were identical in elevation yet shot 2" apart horizontally!
Before I left I shot one round at 200 yards. I figured with the 80 gr load I would be about 10" so I used the appropriate reticle on my scope. Boy was I off. Turns out the bullet being 1/2" high at 100 only dropped 6" at 200! Next time out I'm taking the chronograph and see what my velocity is.

That is a very good start with the Mountaineer! and you really did get the shimming right on! Keep shooting - I bet after you truly have that bore worked it it will even shoot better!

What bullet were you shooting?

Mike I'm shooting a proven bullet for me. Its a .401" (10mm) 200 gr Hornady XTP. When I have more time to work with rhe rifle I'm going to try some full bore bullets. I ran a 250 gr Barnes .451" bullet down the bore and it felt snug but not overly tight. That could be a good start. I also have others i want to try.
you know how it works. Always trying to find the holy grail load.

I certainly know how that goes... keep on searching!