the guy from datamancer is more into making steampunk art, he is a master metalworker but things like the mosin 10 round mag he makes for himself just to see if he can do it. I doubt his creation will ever come to market. that being said all he really did was take some metal and extend the body of the magazine and modify the follower to raise a little higher.
now the person who makes a detachable mosin nagant magazine....thats the person who will get MY money
now the person who makes a detachable mosin nagant magazine....thats the person who will get MY money