US 6,196,455 B1 · Range and drop calculator for use with telescopic gun sights

Abstract

A hand-held analog calculator apparatus, and method for use thereof in the field, in association with firearms. The apparatus permits the user of a high-powered rifle equipped with a telescopic sight having a mildot reticle to quickly determine the range to target and the necessary elevation adjustment to compensate for bullet drop. Various logarithmic scales are disposed upon two rule members which slide parallel past each other. The scales display values corresponding to the mildot measurement, estimated target size, known bullet drop, and the like. By manipulating the rule members to align certain selected marks on particular scales, first the range to target value and then the necessary gun sight elevation adjustment and/or sight hold-over values are displayed on other scales. An interchangeable alternative rule member is provided to permit the invention to be used to calculate in either metric or English dimensional units.

Claims27

Dependent claims

An apparatus, useable with a telescopic sight having a mildot reticle, for determining the distance to a target of a known dimension, the apparatus comprising:

a first rule member;
a second rule member controllably moveable adjacent to said first rule member;
a mildot scale, comprising mil value marks, on said first rule member;
a range scale, comprising range value marks, on said first rule member;
at least one index point on said second rule member proximate to said range scale;
a target dimension scale substantially parallel to said mildot scale, said target dimension scale comprising dimension value marks on said second rule member;
and
wherein when said second rule member is moved to align a dimension value mark corresponding to the known dimension with a selected mil value mark on said mildot scale, one of said at least one index points is substantially aligned with a range value mark corresponding to the distance to the target.

5 more elements

Dependencies are inferred from the claim text.

Range and drop calculator for use with telescopic gun sights

Life of this patent

Range and drop calculator for use with telescopic gun sights

Life of this patent

Abstract

Claims27