A. Get different mags.
B. Put tape on the mags to move them in the magwell to the right location
C. Deal with it and do the "magwell" grip at all times.
Those are all the solutions I've seen to this problem. There is no way to adjust where your gearbox sits in the receiver, and it would be the hopup you would need to move to fix this. Once again, no way to really change the location of it.
Another thing that MAY help is buying a new hopup unit if the bottom nozzle on yours is worn out.