If I want to stake my life on it, it will not be 9mm lol...
I don't think the Hahn mag block allows to hold the bolt open after the last round. Even with Colt OEM mags. The RRA one does.
I found that converted UZI mags were loose in the RRA mag block.
I had once also modified Sten mags to fit a Colt mag block by slimming the top of the mag to fit and cutting a new mag catch.
I don't think the Hahn mag block allows to hold the bolt open after the last round. Even with Colt OEM mags. The RRA one does.
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