What about recoil? Won’t my rangefinder be damaged if I mount it to my rifle?
To understand the probability of damage from recoil to your rangefinder, we must take into account how much force is being applied by common rifle cartridges like the .308, how that force is distributed, and roughly how close that comes to the amount of force necessary to actually damage your rangefinder.
How much force?
The amount of force is not that great. For example, in the case of a .308, the cumulative force of the recoil is about equal to the force of you picking up your rangefinder and squeezing it hard for a few thousandths of a second.
How is the force distributed?
Beyond the actual amount of force is an even more critical factor: How the force is distributed. Sightlok RF-1 uses 3M impact-absorbing rubber to hold the rangefinder and evenly distribute the recoil forces while simultaneously shielding sensitive areas like the buttons, the laser aperture lenses, the ocular, and the ocular lenses from impact. Lastly, when the rangefinder is held in the RF-1 mount, recoil force travels straight back along the bore axis, rather than to corners or edges where impact forces can cause more damage. The result of these mitigating factors is that recoil generates about the same amount of pressure on your rangefinder as you exert when you press the range button.
Typical standards for rangefinder durability
Handheld rangefinders are designed to survive drops of about 3 feet, and the impact from a 3 foot drop can generate several thousand psi of pressure.
How close does recoil come to causing damage?
In the RF-1, recoil presses on any one spot of your rangefinder about as hard as your thumb presses the range button, a few dozen psi at most. A few dozen psi is well under 1% of the pressure your rangefinder is built to survive in a 3-foot drop. At that margin, the chance of a .308 shot damaging a healthy rangefinder in the RF-1 is effectively zero.
No reported failures
In two years of selling the Sightlok RF-1, no customer has reported a rangefinder damaged by recoil.
Recoil tests on video
Below, a US military rifleman tests the Sightlok RF-1 with recoil from two common cartridges.
Sig Sauer KILO1000BDX versus .308 rifle recoil:
Sig Sauer KILO1000BDX versus 6.5 Creedmoor rifle recoil:
