I have several AR15 rifles and carbines. I also have a kind of hodgepodge of Magazines for them. On my last outing I had some problems with the 20 round magazines that came with the first AR I bought right after the Obama election. They are plastic and marked law enforcement/ govt use only. These magazines would feed the first three or four rounds and then stop feeding. When I removed the magazine the remaining rounds were all tipped down into the magazine box nose first or loose. other magazines I have also that are not reliable. If I needed them I believe I would be out of luck. I am wanting to get some reliable magazines or fix the ones I have . What are some good ones that would last a long time? Are there any suggestions for rebuilding the ones I have?