not that I see it on a rifle, the only one - you know it- is my own with the CZ 527 magazine.
I had the idea to build it with a clip and spring loaded feed lip but it dont work because of 7,62x39 cartridge oal in the action.
there must be a sako magazine that can be used with cartridges like 6,5x52 or 35 remington in this rifle.