This is obviously a noob question, I am wondering if it is unwise, or harmful to the ammunition if I unload my carry rounds when I go to the range so I can use my cheap range ammo. I noticed that when I have been doing this I noticed some marks on the casings from them being inserted into the mag. I guess what I am wondering is... by doing this, can this cause the casing to become weaker? I know most of you have an abundance of extra mags, I don't have many, this is the reason I have been doing this. Well... any input is greatly appreciated my fellow Glockers!