Search results
Results From The WOW.Com Content Network
The scope base is the attachment interface on the rifle's receiver, onto which the scope rings or scope mount are fixed. Early telescopic sights almost all have the rings that are fastened directly into tapped screw holes on the receiver, hence having no additional scope base other than the receiver top itself.
A reticle, or reticule [1] [2] also known as a graticule, is a pattern of fine lines or markings built into the eyepiece of an optical device such as a telescopic sight, spotting scope, theodolite, optical microscope or the screen of an oscilloscope, to provide measurement references during visual inspections.
The M21 remained the Army's primary sniper rifle until 1988, when it was replaced by the M24 Sniper Weapon System; some M21s were later re-issued and used in the Iraq War. [12] [3] In standard military use, the M21 uses a 20-round box magazine as the other members of the M14 family and weighs 11 pounds (5.27 kg) without the scope. [13]
The three main technologies employed for long-range shooting—the bolt-action rifle, telescopic rifle scope and machined cartridge ammunition—were developed in the nineteenth century. The first bolt-action rifle was produced in 1824 by the German firearms inventor Johann Nicolaus von Dreyse. The first documented telescopic rifle sight was ...
Civilian AR-15 target sights have an aperture between 1 and 1.15 mm (0.039 and 0.045 in). The aperture on AR-15 military sights have a day aperture of approximately 1.78 mm (0.070 in), and the M16A2 also a night setting with a larger 5.08 mm (0.200 in), and as such the military sight is not strictly a diopter sight in either setting.
In ranged weapons such as firearms and artillery pieces, the act of sighting in or sight-in is a preparatory or corrective calibration of the sights with the goal of having the projectile (e.g. bullet or shell) placed on a predictable impact position in relation to the sight picture.
For precision shooting applications such as varminting or sniping, the iron sights are usually replaced by a telescopic sight. Iron sights may still be fitted alongside other sighting devices (or in the case of some models of optics, incorporated integrally) for back-up usage, if the primary sights are damaged or lost.
The locking bar system allows for even stress to be distributed and prevent canting of the scope mount. Another form of scope canting is caused by the rings themselves. Many Weaver-type mounts, including many Picatinny-type scope rings and even the Redfield Type, have either two or four screws on top of the scope ring that hold the scope in place.