My mom had an old .222 rifle, and I got some reloading equipment. With my reloading equipment, I got a rebate for 500 free bullets. I ordered .224 bullets because I could use it for my mom's rifle, and I could get a .223 rifle and use the bullets for that as well. The extractor on my mom's rifle turned out to be broken, and the gunsmith was unable to locate a replacement. So it pretty much has to be a .223 (especially since it is one of the most popular rifle bullets) or I am stuck with 500 bullets I can't use.