It looks like the back of the cartridge is not being adequately pushed up by the mag spring. But, when I look close the case head appears tight to the feed lips, so while I would check the spring, I suspect the feed lips are the issue. Some gentle sanding of the rear portion of the lips on the bottom side would be what I tried. Basically rounding the edge that contacts the case head. If that doesn't work, then the Ascension Industries 3D printed mags.
Sucks to have multiple mags with the same issue, especially as factory magazines are not cheap.
Indeed it does. I stretched the spring but it doesn’t stay stretched. Very soft. They were going for corrosion resistance, which I can appreciate, over good spring steel. I worked 2 of them over with a diamond file to get them to 75% with 3 down. A couple more weren’t so lucky. Ascension mags on order. I see that the steel lip .223 tikka mags are more money and I’d have to order from the UK. Then they are still stuck with 2.26 OAL. You’d think that they would offer an “M+” variant with steel feed lips, it’s not like the action is short. But the average buyer at Cabelas will take the $40 one over the $70 on every time so I get it.