I was missing around with a Ruger 22 mag loader today and I had to make a mod for it to work on my 22 45 mags. Here's my question...on the front left of the magazine about 2" down from the top is a small protrusion, sort of like the tooth of a food grater, and I don't know what it does. Well, it does get in the way of the plastic HSK loader. I think the mag latch port is further up, nearer the top. ???