Picatinny rail consists of slots with 5.23 mm spaces between one another, which means that it can be used across its entire length. It is simple to mount and interchangeable – if something is made for a Picatinny rail, it will fit regardless of the manufacturer or manufacturing date. It is affordable, resilient and reliable – this is why it so commonly used by professionals and military. Because of all its great qualities, Picatinny rail has been dominating the rail market in the recent years.
Picatinny is a big step forward from the Weaver standard. Weaver has a few predesignated slots while Picatinny has slots all over its surface, allowing the device to be mounted wherever the user finds it fitting. Weaver's slot is 3.8 mm wide, which is why all mounts made for Picatinny will also fit on a Weaver rail while those made for Weaver will not fit on a Picatinny rail. This is one of the main reasons why Picatinny is a far better mounting solution.
EAW is a German company, known for producing top-quality mounts. Their Picatinny rails, which are all made from steel, have a nice finish and come with a unique channel in the middle, allowing the user to clearly see the rifle's sights. Screws are included. EAW chooses only the best materials for their products. All of these great features; however, come at quite a steep price.
Heym is a firearms manufacturer from Germany, founded in 1865 – they have over 150 years of experience. Their rifles, known for great handling, durability and accuracy, are still manufactured by hand.
Heym SR 21's action body is very solid. This is a successor to SR 20 and was introduced in 2001. The bolt is nearly fully shrouded, and the rifle has a wooden bolt knob to match the stock. It is equipped with a traditional bolt action but there are a few innovations to it. One of them is the exchange barrel system (to fire a different caliber, the user has to change both barrel and receiver). It features a removable magazine.There are two emergency gas ports on the front bridge section, and three locking lugs on the bolt. Its push-fed bolt action operates with a 60-degree arc movement and is very smooth. Safety has three positions. It is chambered for .25-06 Rem., .243 Win., 6x62 Freres, 6.5x55SM, 6.5x57 mm, 6.5x65RWS, .270 Win., 7x64 mm, .308 Win., .30-06 Sprg., 8x57 mm and 9.3x62 mm. For some extra cost, it can also be supplied in .22-250 Rem., 7x57 and 8x64S. Sr 21 G is made for 8x68S, 7 mm Rem. Mag., .300 Win. Mag. and .338 Win. Mag.
Riflescope mounts made for Heym SR 21 will not fit Heym SR 20 because these rifles have actions of different dimensions.
Heym SR 21 has a similar action as Heym SR 30. The radiuses of the mounting surfaces are the same but there is a difference in B distance (see the picture below). This is why two-piece mounts made for Heym SR 21 will fit Heym SR 30 while one-piece mounts made for Heym SR 21 will not fit Heym SR 30.
A: 21.9 mm
B: 110.9 mm
C: 12.8 mm
BHU: 1.5 mm
Remove all the stains (grease, oil etc.) from the rifle's receiver with a cleaning fluid (acetone). Once the surface is clean and dry, check whether the screws match the rail and the holes on the receiver. Make sure that the Picatinny rail is compatible with the rifle by inspecting the mounting holes on both. Before mounting the rail permanently, apply a minimal amount of thread-locking fluid 278 or 648 on screws and contact surfaces. Be careful not to get the fluid in or near the mounting holes. Carefully clean the remaining excess fluid around the rail with a cleaning fluid. Using a torque driver, screw the screws appropriately (up to 2.2 Nm) – do not overtighten.
The product has a warranty period of 30 years.
|Mount series||EAW Picatinny Rails|
|Suitable for||Heym SR 21|
A, B and C markings refer to the distances between holes on the rail/mount. A is the distance between the front two holes on the rail/mount.
A, B and C markings refer to the distances between holes on the rail/mount. B is the distance between the holes in the middle (usually, that is the distance between the 2nd and 3rd hole on the rail/mount).
A, B and C markings refer to the distances between holes on the rail/mount. C is the distance between the rear two holes on the rail/mount.
BH stands for Bauhöhe (ger.) which means overall height. It is measured from the mounting surface of the rifle to the lower surface of the riflescope's tube.
Often, the elevation adjustment that the riflescope offers is not adequate to compensate for the bullet drop when shooting at long range. When the riflescope runs of out of elevation, a mount with an inclination is needed. 20 MOA is the most common inclination. With it, the user gains 58.2 cm / 100 m of additional elevation range when shooting at the range of 100 m. This is approx. 5.8 Mrad of elevation.
(Posted on 23/05/2017)