I second what was said above. A friend of mine had the same problem..
On a second note - and related to this kind of magazines: is it normal for the mag
to wobble a little when sitting in place? The bolt still catches the BB and loads it and the mag valve sits below the bolt..but it still wobbles a little in the sense that you could push it a little more towards the receiver or tilt it a bit.
I think this is kinda normal and allows the bolt to slide easily without tearing against the valve.. But I might have to shim the receiver to make the mag sit more on top..hence my doubt.
I used the thread since it is a similar question and same title I would have used
I hope it is ok.