ACTUAL CONFIRMATION if CZ-527 7.62x39 Mags work for 300-221 rounds?

[amafrank]

In my opinion pressing the ribs out is a lot more difficult and likely to damage the mag. All that metal has to go somewhere when you squish it. Its not likely to go back where it came from so your mag will end up rippled or too long or who knows....good idea but I don't think it will work reasonably without some heavy machinery. On the other hand, milling out the ribs and then soldering or brazing in patch plates would be pretty easy. In reality the patch plates don't have to be fitted to the slot (though thats easy to do) but can overlap the edges. If you mill them out wide so there is no flange left inside the mag you can solder the patch plates inside the mag too. It fills the hole so crap won't get inside but doesn't distort the mag body. A last suggestion here was done by a customer on one of the mags I modded for him. He put some clear tape over the slot, inside and out, to seal it while making it possible to see how many rounds were left through the clearly visible slot. Slot covered for dirt exclusion but round counter in place.

Hope that helps
Frank

[kurtz]

On the aluminum AR mags I pushed the ribs in about .070" each side, using a wood surround and aluminum press piece was all that was needed and they worked out fine.....no growth or warpage...

I believe JD modified some in a similar fashion using a wood push piece and hammering it in to open the mag up a little....the ones he supplied with my AR had the top 2" or so milled out

the steel cz mag, and the way the rib has a bevel surround is gonna be different....that's why I figured the steel surround would be needed to keep it from growing when pressed, much more pressure...but hey, if somebody can make aluminum work I'm not gonna throw water on their enthusiasm or experimenting....I think it would be neat if it works out....