Dovetail rail
A dovetail rail or dovetail mount can refer to several types of brackets found on firearms primarily for mounting sights. Dovetail rails usually refer to a dovetail running parallell to the bore (i.e. an 11 mm rail or a picatinny rail) to be used for mounting a scope or diopter sight to a rifle. These are sometimes also called "tip-off" mounts, and allow the user to easily take on or off the sight. Dovetail mount can also refer to a dovetail track running perpendicular to the bore, see "Other uses" below.
Dovetails come in several different types and sizes depending on manufacturer, but the most common are the 11 mm and 3⁄8 inch (9.5 mm). Some other less known, but currently commercially available dovetail mounts, are 12, 13, 13.5, 14, 14.5, 16, 16.5, 17 and 19 mm.
While the well standardized picatinny rail mount (and its less standardized predecessor the Weaver rail) is most known in the U.S., many European gun manufacturers offer proprietary scope base receiver mounting systems for their guns, for example Sako has tapered dovetails, Tikka use a 16 mm dovetail, and there are other solutions such as the Blaser Saddle Mount or Recknagel Swing Mount. Dovetail mounts are today mostly found on light recoiling air guns, but can also be found on some modern rifles for hunting and sport shooting using smokeless powder, although other options such as the picatinny rail are becoming more popular.
Some examples of rifles with different types of rails:
Dovetail mount can also refer to a dovetail track running perpendicular to the bore, often used for smaller front sights posts and rear sights blades found on handguns and some rifles. This mounting method is ment as a semi permanant friction fit mounting solution where a slot is milled, for instance in the slide of a pistol, and a sight with a corresponding dovetail is punched or drifted into that slot.
Rear sights are offered in many dovetail cut profiles which are non-compatible, and some well known (and incompatible) cut profiles are those from sight manufacturers such as Novak, BoMar, LPA/TRT, Kimber or the 1911 mil standard. Additionally many pistol manufacturers have their own proprietary dovetail cut profiles.
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