From what I understand, that’s the only thing that duckbill sks 30’s are good for. These unconventional lights are awesome, I can’t wait to see what you do next.
That style of mag was a jamomatic in my SKS... The polymer Tapco mag turned out to be much more reliable. Nothing beats the reliability and easy reload of the factory box with stripper clips. Of course the polymer lacks the heat sinking for flashlight modifications...