It would seem to me that if one could make some modifications to the magazine lock plate and the red follower (both plastic), you should be able to get 11-12 rounds in the magazine. I do not see how one could not get more without major modification, it looks as if CZ did their level best to ensure one could NOT easily expand round capacity.
Basically my idea is:
1 - shave a bit of material off the bottom of the red follower... not too much
2 - reshape the magazine lock plate such that it is thinner, thus allowing it to sit further down in the magazine... One cannot just cut off part of the follower as this will:
a) take away the lock button (although its not really needed, friction locks the base of the mag on pretty good as is) and more importantly
b) the magazine spring will bind, as it relies on that little tab sticking up from the lock plate to keep it 'stable'
Therefore one would have to grind down the lock plate from the top and effectively extend the tab.
If I had to guess, I'd say that I could end up getting 12+0 out of the mag (ie, 12 will fit but not likely enough room to allow the magazine to insert with the bolt closed, as that presses the rounds down ever so slightly (about 1/2 a round worth).
I'd love to try this if I could get ahold of some spare followers and lock plates... Not gonna screw up the originals! Anyone know where/how I can order some?
btw its not too hard to make an 18rd magazine from two 10rd mags and some good tape
