Personally, I think the .300 WSM is superfluous at minimum, pointless at worst. The short, fat case is a good idea and may be a bit more accurate than longer caes, but if you need something the size of a .300 mag then you really do want all the capacity for both powder and long bullets that you can get.
That being said, I think short mags in 7mm or less make great possibilities, with numbers from 6mm - .277 being ideal. I' d love to see .25 cal or 6.5mm short mags...if we had those cartridges, deer hunters could put away their cannon and still be able to tote a sensible " Magnum" around the woods.
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