I have an ar-30 in 300wim mag. I wanted to get a couple extra mags for it and was looking for some 10 rounders. I was unable to locate any. I am contemplating making some but I don't want to go thru the trouble of programing, waterjetting and machining the followers if I am only going to make a couple. I Think the 300 and 338 use the same mag. I have no idea about the 308 version. If you have any interest post it below and I will go from there. Thanks Chris.