What .22 magnum semi auto rifle that uses quick detachable magazines ever came close to the popularity of the Ruger model 10/22 (the .22 LR version)?
There have to be a lot of a particular model of gun out in the hands of the American public before manufactures (both OEM and aftermarket) will think about offering high-capacity mags.
Besides, the cost of 22 magnum ammo is a strong disincentive
for people to might want to do mag dumps an entire box of 50 at a time!