So I adressed the magazine fitment issue last night. Removed the action from the stock so I could see what was going on and that made the problem clear.

I used a vice grip and was able to progressively adjust the rear guide lips until it fitted without rattling and had enough tension to not be slopping around up and down. Lateral guiding was improved, but if I make a replacement for their tin insert in the stock that actually has the right shape for the magazine, that will permanently solve the lateral clearance issue.

Now the magazines do not seem to create a problem with blocking the bolt anymore. I used my drum sander and dremel to remove the sharp edges at the front of the magazine. I had to file the slot at the back of the magazine guide wide enough for the latch to work, after I made the guide fit the rail snug.

So after all that, I took a look down the bore last night and about had a heart attack in that the rifling was barely visible ? Looking around, the info I found regarding rifling was at green mountain which says it is 0.219" bore and 0.224" groove diameter. So the rifling is only 2.5 thou high ? Krieger shows 0.217" / 0.222" bore/groove so 0.001" smaller, but same height for the rifling. I have had a few 223 rifles in my time and they are 0.218/0.224 so 0.003" high rifling which does not sound a whole lot different to the 22 mag.

So right now I don't know what to think regarding the bore, it certainly does not look anything like any other rifle bore I have ever seen. The bore on my DE 44 mag with its polygonal rifling was the closest in appearance, but I'm pretty sure that there is nothing exotic about the rifling in my barrel.

The crown is also crappy on my barrel, it seems to have a chamfer between the bore and the face of the crown, which I have never seen on any barrel that ever shot well. Its almost as if it is the remnant of a center drill from the turning process that was not removed during crowning. I can re-crown the barrel easy enough, but before I do that I need to know if the bore itself is good.