Oly sells aftermarket re-worked Sten mags with a 1" piece of channel box welded on teh back that fits pretty nice into the mag well, eliminating the need for the mag block.
They have a hole for the mag release catch, and your mags drop free and the mag release works just like your standard AR mags.
Which is good, cuz you wanna practice your mag releases and reloads the EXACT same way as with your .223 AR
Or if yer handy with metal, you could fabricate some yourself REAL easy.
In fact, I may try that myself.
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