7.62 to 5.56 ejector. to 9mm hammer spring (maybe) and ejector for sure. It may or may not run well with the rifle hammer spring and might be a little harder to cock. Some use a .40cal spring and pretty much get away with everything. The registered pack my friend has that I run in my 9mm sometimes has a rifle hammer spring and all I have to do to use it is swap the ejectors and drop the pack in.