Checkmate makes all the GI mags and has for years, that's why I bought some of them. They are identical to the SA mags. I junked both of my no-name magazines promptly and used them for experimentation with feed angles etc., but I think all that was really wrong with them is they spread under pressure (thin steel) and weren't latching in so the front tabs were firm against the top of the mag well. Magazines are not the problem anymore with mine feeding.
Those pictures help, but they don't show the feed angle of the other 19 rounds, which are my problem. All my magazines feed the last round just like in your pictures, it's because of the shape of the follower, it actually turns the nose of the round up and dead center of the chamber. See how the case body isn't parallel to the magazine lip? If they all did that, there would be no issue. But when two or more are stacked in there, like in the pic I posted, the noses kick out more parallel to the action and don't angle up so much, which is why the blunt-nosed bullets hit the barrel recess and stop dead. Stick two dummy rounds in there with the Accurate bullet loaded in them, let the bolt fly home on the first one, and see if it doesn't take a big chunk out of the nose. Everything else on yours and mine look the same, so I can't understand why you don't have feed issues with your Accurate bullets any more than you can understand why I do.
We obviously have very different chambers and throats, mine has a parallel .310" freebore less than half as long as what yours is, and the chamber neck is much tighter with a taper to it. Barrel is steel with the standard pencil contour. Behind the op rod guide, it's just slightly larger than in front, but not "full diameter" by a long shot. It only weighs nine pounds without optics and an empty magazine installed, but has the full 22" barrel and NM flash suppressor.
