Abstract: A barrel measuring device for accurate measurement of all internal dimensions and barrel wall thickness of a gun, tube, pipe or cylinder is comprised of a fixed probe transversely attached to a cross member at a distal end. A second probe transversely attached to a body member proximate to the fixed probe, said body member and second probe slidaby moveable along the axis of the cross member. A measurement device attached to the body member and second probe for recording of the diameter proportional to the degree of expansion of the fixed and second probe within the barrel. A recoil means for expansion contained with the cross member and attached to the body member coupled with the second probe providing an expansion pressure between the probes for measurement with the measuring device.

Abstract: A barrel measuring device for accurate measurement of all internal dimensions and barrel wall thickness of a gun, tube, pipe or cylinder is comprised of a fixed probe transversely attached to a cross member at a distal end. A second probe transversely attached to a body member proximate to the fixed probe, said body member and second probe slidaby moveable along the axis of the cross member. A measurement device attached to the body member and second probe for recording of the diameter proportional to the degree of expansion of the fixed and second probe within the barrel. A recoil means for expansion contained with the cross member and attached to the body member coupled with the second probe providing an expansion pressure between the probes for measurement with the measuring device.

Abstract: A firearm measuring device for measuring all external dimensions of a firearm is comprised of an elongated rectangular caliper body member having measurement indicia inscribed thereon. A pair of jaws affixed on the caliper body member, one jaw affixed to a carriage and moveable along the caliper body member, a second jaw permanently affixed at one end of the caliper body member. A drop meter affixed to the caliper body member adjacent to the fixed jaw and vertically adjustable along the length of the drop meter by a channel within the length of the drop meter. The drop meter having a measurement indicia inscribed thereon. An extension member for attachment to the caliper body member having a bottom tooth-shaped configuration which is positioned on a gun barrel. The extension member having a magnetic means recessed within the extension member for securing the extension member in combination with the caliper body to the gun barrel eliminating need of holding the device during operation.