The lack of capacity in limited is an issue. 18 is the most I have seen anyone run reliably. But for open, capacity isn't a problem. I have assembled mags that measure 169.8mm long that run reliably with 29rnds. With a different follower I have been able to get 30 but have had issues with occasional nosedives. I am going to make another basepad to run my mags out to max legal length and see if I can get 30rnds to run reliably.