Patent ID: 8819985

Claim:
A sight level for a firearm assembly comprising a firearm and a sighting apparatus defining a sight line, where the firearm comprises a barrel having a bore defining a centerline and the centerline and the sight line define a shooting plane, the sight level comprising: a main body and a strap, where the main body defines a first hinge part and a fastening portion, where the first hinge part defines a first notch, and the strap defines a second hinge part defining a second notch, the first notch is configured such that a portion of the second hinge part may pass through the first notch, and the second notch is configured such that a portion of the first hinge part may pass through the second notch; and a level indicator operatively coupled to the main body for rotation about a rotation axis; wherein the sight level is detachably attachable to the sighting apparatus by passing a portion of the second hinge part through the first notch while passing a portion of first hinge part through the second notch and then displacing one of the main body and the strap along a line parallel to the sight line defined by the sighting apparatus relative to the other of the main body and the strap such that the first and second hinge parts interlock; and when the sight level is attached to the sighting apparatus, the main body and the strap are configured to engage the sighting apparatus such that the rotation axis is substantially parallel to the centerline, the level indicator rotates about the rotation axis between a home position in which the level indicator lies at least partly within shooting plane, and an extended position in which the level indicator is spaced from the shooting plane, and the level indicator is spaced vertically above the sighting apparatus in the home position and in the extended position.