These extended magazine boxes are built to allow longer bullet seating, and thus a longer than standard overall cartridge length. Installation requires alterations to the receiver, bolt stop and ejection port.
- It is the center feed design, and allows for an O.A.L. of approx. 4.000"
- The box is normally sold with an F-10 follower
- Outside length 4.070", inside length 3.990"
- Requires gunsmithing/fitting for installation