Recently purchased an XD 40 S & W with 12 rd mags. Initially getting 12 rounds in the mag required a lot of effort, I had to resort to a speed loader to compress the spring and follower to get the 11th and 12th round in. Now when I insert the magazine it does not fully engage against the retainer clip. If I apply extra pressure it will "click" in place but the pressure against the clip is such that the magazine will not drop when the release button is pushed. This only happens when the 12th round is in the mag. My questions are: Is this normal and will it ease up as the springs loosen up? why the 12th round sinced the top round always occupies the same space? What could the top round be pressing up against that is causing the excess tension? Thanks for any replies.