Originally Posted by lucznik
Perhaps but, is the curve an integral and necessary part of their design, or just a cosmetic feature to make them look cooler?
For example,the mags on an AK are rather dramatically curved whereas those of an AR tend to be more strait, even when they are chambered for the same 7.62x39 cartridge.
The only AR mags I've seen for the 7.62X39 have just as much of a pronounced curve as AK mags. They're a bit straighter with the .223/5.56.
Its an integral design feature. They have to fit the magazine to the round. The .223/5.56 doesn't taper as much between the base and the shoulder, therefore the curve isn't as pronounced. The 7.62X39 has a pretty pronounced taper, comparatively, from the base to the shoulder. Ergo, a more pronounced curve.
Now, while .22LR and mag have no taper to their casings, its a rimmed cartridge. Meaning the base is still wider than the case mouth. Not so with most, if not all, ACP style handgun cartridges which use straight magazine boxes. But because it's so with .22's, they must use a curved mag too. And to top it off, the protruding case rim presents it's own lost of problems in the form of hangups, where rims get snagged on each other.
How the hell kel tec made a mag that semi works, I'll never quite understand. But this is why you just don't see magazine fed weapons that use a rimmed cartridge very often. A lot of trouble to overcome.