Ruger 77/22 Magazines have a rotary function. The magazine holds 10 rounds that each have their own slot in the rotary magazine. The hard polymer and steel feed are durable and will last for years. Stop wasting time reloading at the range or in the field and pick up an additional magazine for your 77/22. This rotary magazine is a factory original from Ruger. Factory original parts are made to the same specifications that your original parts were.