Choosing the correct mounts
Full selection of Hawke Mounts
Selecting the correct mounts is a crucial part of setting up your equipment and ensuring your get the most out of your Hawke scope. There are several key factors to decide when making your selection. Here is a quick guide to help you through the process:
TYPE OF RAIL
9-11mm Dovetail
9-11mm Dovetail rails are commonly found on Air Rifles and some Center and Rim Fire Rifles. The rifle's rail (or receiver) has two long grooves, one either side, that run down the length of the rail. It is without any horizontal notches/grooves and often has one or a few recoil holes on the top of the rail.
For any scope being fitted on a 9-11mm Dovetail rail a set of 9-11mm Dovetail mounts will be needed (as seen below):
Weaver / Picatinny
Weaver and Picatinny rails are commonly found on Hunting Rifles, Assault Rifles and various other heavy recoil rifles. It is also possible to place Weaver and Picatinny adapter rails on a rifle so Weaver mounts can be used. The distinguishable feature of Weaver and Picatinny rails is the repeating horizontal grooves that run down the length of the rail. These grooves act as recoil stops for the mounts that are fitted around them.
For any scope being fitted on a Weaver or Picatinny rail a set of Weaver mounts will be needed (as seen below):
The key difference between Weaver and Picatinny lies in the placement of the recoil grooves and the width of the grooves. Picatinny grooves have a center-to-center width of .394” (10mm). The placement of these grooves has to be consistent in order for it to be a true Picatinny system. Weaver systems have a .180” (4.57mm) width of recoil groove and are not necessarily consistent in a center-to-center measurement from one groove to the next.
MOUNT DIAMETER – 1” or 30mm
All Hawke scope mounts come in two different sizes, 1" or 30mm. These sizes relate to the diameter of the scope's tube.
MOUNT HEIGHT
The required mount height is determined by the size of the scope's objective lens. Ultimately, correct sized mounts will ensure the scope clears the top of the barrel, while not leaving too much of a gap.
Mount heights are often split into three different sizes; Low, Medium and High.
To ensure the correct size mount is fitted we need to take a couple of measurements. The height from the bottom of the mount to the middle of the scope ring is listed on each mount's webpage.
This height must be more than half of the scope's widest point (normally the objective bell of the scope). This will ensure the scope clears the barrel when sat in the scope mounts.
Traditionally shooters will try and fit the scope with minimal clearance above the barrel. This helps the line of sight be nearer to the bullet trajectory which will give better results when changing target distance.
Some rifles' rails will sit slightly higher than the barrel. If the scope's objective bell is going to be above the barrel then this extra height difference can be taken into account.
Example
Here we will calculate what mounts are needed to fit a Hawke Sidewinder 30 SF 4-16x50 to an Anschütz .17 HMR with 9-11mm Dovetail rail.
We know the Hawke Sidewinder has a 30mm scope tube and that the Anschütz .17 HMR has a 9-11mm Dovetail rail, so all we must do is calculate the required height of the mount.
The Sidewinder's 50mm objective lens means that the objective bell has a diameter of 56mm (see below):
As mentioned before, we now half this 56mm diameter to give us a measurement of 28mm. This is the minimum height from the base of the mount to the middle of the scope ring. The 30mm 9-11mm Dovetail mounts come in two sizes; medium and high. The medium mounts measure 28mm and the high mounts measure 35mm. As we want to ensure there is enough clearance that the scope is not touching the barrel we will in this instance choose the high mounts.
