Scope dovetail rails: 11 mm (European) and 3/8 in (US), and Weaver — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/scope-dovetail-rails/  (sheet CC BY 4.0)
Basis: Published dimensions only (Optics Trade technical article; Brownells GunTech via AccurateShooter); groove depth and height are not standardized, so no file
Catalog version: 2026-10-20

Sizes: see table below
- Airguns, rimfire rifles and many airsoft and crossbow scopes use a plain dovetail instead of Picatinny.
- 11 mm dovetail: 11 mm across the top with 60° sides (the European standard). 3/8 in dovetail: 12.7 mm across the top with 45° sides (the US standard); the 3/8 in is measured across the bottom. Their depths and heights vary by maker, so Xem publishes no file: measure your rail's height before designing a clamp.
- Weaver: grooves .180 in wide, with no standard centre-to-centre spacing.
- Picatinny (MIL-STD-1913) is fully specified: see its page for the complete profile and files.

rail  top width  side angle  groove
11 mm dovetail  11 mm  60°  none
3/8 in dovetail  12.7 mm (3/8 in across the bottom)  45°  none
Weaver  not standardized  —  .180 in wide, spacing not standardized

Files elsewhere (not hosted by Xem Studio; license as stated by the publisher):
- Optics Trade: 11 mm and 3/8" dovetails — web — Publisher's page; dimensions are facts — https://www.optics-trade.eu/blog/11-mm-and-3-8-dovetails/
- AccurateShooter (Brownells GunTech): Picatinny vs. Weaver rail specifications — web — Publisher's page; dimensions are facts — https://bulletin.accurateshooter.com/?p=5211

No true-size file yet: the published figures do not fix the whole shape; a measured scan is planned.
API: https://xemstudio.com/api/geometry?object=scope-dovetail-rails