Well put together vid, thanks for sharing.
Much as I like pellet firing CO2 pistols, I have both the circular mag CP88 and CP99 Walthers, when it comes to blowback pistols, it's all in the fun not accuracy, and BB pistols do it for me.
Talking about expensive magazines, the one used in the PPQ is the two piece, pinned together type. In my experience these are the only ones that I've ever seen broken. What happens is ham fisted, or maybe just inexperienced owners, use excessive force on the CO2 bulb screw resulting in one or both of the alloy tangs breaking off the top part. A comparison of various mags in my pic, all BB. The last three are very robust being cast in one piece.
The first one is from my H & K VP9, built much the same as yours, next to it is the fully enclosed Beretta 92A1, then the Remington 1911, at the end my Luger PO8.
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