What Causes Mirage?
Cold air is denser than warm air, and therefore has a greater refractive index. As light passes from colder air across a sharp boundary to significantly warmer air, the light rays bend away from the direction of the temperature gradient.
When light rays pass from hotter to cooler, they bend toward the direction of the gradient.
If the air near the ground is warmer than the air higher up, the light rays bend in a concave, upward trajectory — something we commonly see through our rifle optics. In the case where the air is cooler on the ground or near the ground than the air higher up, the light rays curve downward.
There are three types of mirage: inferior, superior, and Fata Morgana. Precision shooters typically encounter the inferior mirage.
The inferior mirage is also known as the highway mirage, or desert mirage, and looks as if water or oil is on or near the target. With inferior mirages, the target’s image is distorted. It may be vibrating, vertically extended (towering), or horizontally extended (stooping).
If there are several temperature layers, several mirages may mix, perhaps causing double images.
Another type of mirage that precision shooters may encounter is known as barrel mirage. Barrel mirage occurs as the rifle barrel heats up, typically when the shooter fires an excess of 1-7 rounds without a sustained break in-between shots. The barrel mirage will occur faster when the shooter uses a suppressor.
How Our Cover Works
LEGIONNAIRE CUSTOM MIRAGE SHIELD
The custom made cover prevents mirage from your suppressor interfering with your optical image of the target and the adverse effects on accuracy as a result. As it is custom made it will always be the perfect fit for your
Eliminating mirage is accomplished by the use of cutting edge insulating materials. Designed and manufactured in south Africa, the cover is a first of its kind in southern Africa and one of a very few in the world being offered in custom sizes. The Cover is extremely lightweight, and only measures from 3mm in Total thickness. The Cover is certified to temperatures of up to 200 Degrees Celsius.
During competition shooting or whenever the shooter fires 3 or more shots, especially during warm, humid summer days, the barrel and suppressor of the rifle heats up significantly. Because the Suppressor has a greater surface area than the barrel the mirage effect becomes immediately apparent as viewed through the rifle scope especially on higher magnification. The effect can be reduced somewhat by reducing magnification, but unless the Suppressor is allowed to cool down completely the hazy effect will not go away.
The Cover is designed to minimise heat transfer between the Suppressor Surface and outside Surface of the Cover. The Cover will feel warm to the touch, but will be considerably cooler than the exterior of the suppressor itself. And not warm enough to cause mirage through your rifle scope. Because of the simple mounting system the cover can be easily removed after firing to assist with heat dissipation and also making the handling of a hot Suppressor easier. No more burnt fingers.
The Cover has a built in retention system to ensure it will not move even on the heaviest of recoiling rifles. As the cover has a 100% Cotton Canvas exterior, it will resist catching on brush even when used on hunting rifles in a bushveld setup.
Can The Cover Damage Your Rifle?
This is a frequent question and often leads to heated discussions.
The short answer however is No!
If you shoot your rifle in such a way that the suppressor becomes red hot, chances are that you have already ruined your rifle. The temperature and pressure in the throat area of the rifle is substantially higher than at the muzzle.
Unfortunately the old saying goes, “there’s no free lunch”
Yes by adding the cover you are containing the heat in the suppressor, this is the entire purpose of any cover meant to assist in mirage dissipation.
But even if left on the suppressor after firing the cover will not damage you barrel or your firearm.
Improper suppressor design (too much blowback onto crown) or poor barrel cleaning and suppressor cleaning routines will have a much worse effect on your equipment than any cover will ever have.