My SA 9mm feeds rounds with a 1.135" OAL or 1.175" equally well. I would like to load them out to 1.200", but the barrel would need to be throated more to do that. I have found the McCormick 38 Super 10 rd. mags to work well. For some reason I cannot get 10 rds of 9mm to work in a Wilson mag without swapping in a McCormick follower.