I was having that problem and thought it was normal, then I bought a new magazine (yes, I actually found one) and that one slid in easily with a nice "click" just like an empty mag. I took the follower out of the new one and and old one and compared them. They didn't look anything alike. I called S&W customer service and they said "Yes, the followers have been changed, you can send your magazines back and we'll exchange them, or do you just want me to send you some followers"? I opted for the followers, hopefully they will work the same as my new magazine. As I stated earlier, I can get the 12th round in loading it by hand but apparently there isn't enough "give" in the stack of rounds to easily seat the mag with the slide forward. I'll report back after I get the new followers. I've attached a couple of pictures of the new and old followers that I took and was going to send to S&W but didn't have to.