At the range with my new Springfield SS 1911-A1 optimized. I've always thought the slide was a bit tight but on at least two occasions I've seen the slide hang up for just a bit before closing. Seems to happen on the second 8 round mag and then all is well thereafter. If I don't clean it (say, two sessions in one day) It doesn't do it on the second session. But if I clean and oil, it does it every time. What is the best way to loosen the slide a bit?