The AR-7 Explorer, was heavily based on Stoner’s earlier version, known as the AR-5. The AR-5 was a .22 Hornet-chambered take-down bolt-action rifle designed for pilots who were shot down to be used for survival in hostile conditions. Henry Arms made a few major changes to the original AR-7 concept. The largest one was made out of stock. Henry introduced a deeper finish, with grooves in the grip area that give better handling characteristics, instead of using a slick fiber glass style as seen in the original. Instead of one, they revamped the inside to store three magazines, with the third still left in the magazine.
Finally, for the consumer to mount a scope as an option, they added a rail. It’s a 22 tip-off sort, not a Picatinny rail, and we suggest that you leave the rifle in its mounted state if you plan to install optics, as opposed to taking it down, because you will lose your zero.