This is the Ruger BX-15 Magnum magazine, designed for the Ruger Precision Rimfire it is also compatible with all other Ruger .22WMR and .17HMR rifles.
Based on the BX-15 and BX-25 magazines it features a tough polymer body with the same steel feed lips as the standard JMX-1 rotary magazines. steel locking lugs and fastenings and is fully strippable for cleaning.
Fits the following models chambered in .22WMR or .17 HMR:
- Ruger Precision Rimfire
- Ruger 10/22 magnum
- Ruger 77/17
- Ruger 77/22
- Ruger American Rimfire