Eotech | Cold Weather Distortion | Reticle Fade | Thermal Drift | Parallax Issues

Eotech | Cold Weather Distortion | Reticle Fade | Thermal Drift | Parallax Issues

Dear Valued EOTech Customer:

EOTech values your business and is committed to providing you with the highest quality products. Provided below is information on four issues that may affect your EOTech Holographic Weapon Sight (“HWS”). EOTech has not issued a recall of any of its sights, and many of our customers continue to use their sights regularly. EOTech nonetheless wants you to be satisfied and is offering refunds at your option.

Depending on the age of your sight and the ways in which you use it, you might or might not be affected by these issues. Many HWS users experience no issues with their EOTech sights especially if (for example) the sight is used in close-quarter ranges, the target is in the center of the window, or the sight is re-zeroed frequently. We hope the information presented below is helpful.

Eotech Cold Weather Distortion

Cold weather distortion generally does not affect EOTech-branded HWS manufactured after March 2008. The historical issue with cold weather distortion was that the HWS’s aiming dot experienced distortion of size and shape when the sight was exposed to temperatures below 32° F. This became worse as the temperature approached -40° F. It had virtually no effect in warmer temperatures or at the close-quarter ranges where the HWS is typically used, because at those closer distances the distortion would not have a significant effect on the point of impact. Although generally unnoticeable to the naked eye, the distortion existed at colder temperatures.

Impact: Generally none for EOTech-branded sights manufactured after March 2008. For sights manufactured earlier, the sights affected are those used in cold weather for longer range shooting.

Eotech Reticle Fade (Moisture Incursion)

Reticle fade as a result of moisture incursion generally does not affect sights manufactured after July 2014. Even for sights manufactured before that date, the effect may not be substantial. The issue is that atmospheric moisture conditions can lead to the HWS’s reticle fading or eventually disappearing. It typically is noticeable first when the reticle appears to dim at the edges of the sight window. The sight’s age and environmental exposure are factors that accelerate reticle dimming. In many cases, however, this condition can be mitigated by increasing the brightness of the reticle, using the sight’s brightness controls.

Impact: None for any sights manufactured after July 2014. Potentially minimal impact for sights manufactured before that date, depending on the sight’s age and use. Whether your sight will experience reticle fade will depend on the factors discussed above.

Eotech Thermal Drift

EOTech’s sights experience a point of impact shift away from the point of aim when the sight is exposed to a temperature different from the temperature at which the sight was zeroed. After zeroing the sight at or near ambient temperature (73°F), the zero position will shift during operating temperature changes. The sight has the potential to shift approximately +/- 5 Minutes of Angle (“MOA”) at -40°F and 122°F. Due to thermal drift, the sight may not return to zero. The sights have the potential of approximately a +/- 2 MOA zero shift upon return to ambient (73°F) after being exposed to any temperature between -40°F and 122°F.

This shift results from natural thermal expansion or contraction that is present in various materials as they are heated or cooled, and is greater the more extreme the temperature change. For example, when a sight is zeroed at 70˚ F then acclimated to 50˚ F, less shift will occur. On the other hand, if zeroed at 70˚ F, then acclimated to 0˚ F, more shift occurs. The shift may not be significant to shooters who use their sights at close-quarters ranges. For instance, 5 MOA is a shift of 1.25 inches at 25 yards, and is 5 inches at 100 yards. It also is worth noting that thermal effects are evidenced to varying degrees in common optics, as well as in rifle barrels and ammunition as the environmental conditions change. In all events, to achieve optimum accuracy, the sight zero should be verified whenever the sight is exposed to marked temperature changes, and the sight should be re-zeroed as necessary.

There is no repair currently available to eliminate thermal drift. If your HWS experiences a degree of thermal drift that is unacceptable to you, and re-zeroing does not address the issue to your satisfaction, please contact EOTech, as described below, to obtain a refund of the purchase price.

Impact: The sight’s zero will be affected at varying operating temperatures. This may be minimal for sights used at close-quarter ranges and may be corrected by re-zeroing the sight.

Eotech Parallax

All optics experience varying degrees of parallax depending on use and operating conditions. Parallax is an apparent change in the point of aim resulting from a change in the position of the shooter. EOTech’s sights have little parallax when the reticle is in the center of the viewing window, which is the optimum sighting position and also is the correct place for zeroing the sight. On the other hand, if the user is looking through the sight at the outer edge of the sight window – an off-axis view – the parallax error might be up to 4±3 MOA (or a total of 14 MOA across the viewing window) at 71˚ F (for a sight properly zeroed). In other words, parallax can increase as the user’s view approaches the edge of the EOTech viewing window. To put this possible amount of off-axis error into perspective, 7 MOA equates to 1.75 inches at 25 yards or 7 inches at 100 yards. Viewing through the center of the window achieves the least parallax error. Parallax may increase as temperature changes from 71˚ F. At operating temperature extremes of -40˚ F or 122˚ F, there may be an additional 4 MOA of parallax.

Impact: Virtually none if the shooter is aiming through the center of the sight. Relatively small effect at close-quarter ranges, if the shooter is aiming through the very edge of the sight’s window. As described above, the effect is greater when the shooter is aiming off-center, at longer ranges, or at temperature extremes.

Customer Return Policy
We sincerely appreciate your business and will do our utmost to ensure your satisfaction. If you desire a full refund of your purchase price (plus shipping costs), please let us know by completing the form at www.eotechinc.com/return-authorization-request-form.

If you have any questions, please call our Customer Service Department at (888) 368-4656 or email us at support.eotech@L-3com.com.


The EOTech Team

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Aero Precision M5E1 FDE 308AR 16″ Barrel

Aero Precision M5E1 308 AR 16 Inch EK-12 Handguard FDE Cerakote APCR308012

Aero Precision M5E1 308 AR 16 Inch EK-12 Handguard FDE Cerakote APCR308012

Aero Precision M5E1 FDE 308AR 16″ Barrel


M5E1 Complete Rifle, 16″ .308 Barrel, EK-12 Handguard – FDE Cerakote APCR308012 The Aero Precision M5E1 Complete Rifle features a custom integrated upper receiver and hand guard system. This extremely rigid design allows for a stronger handguard mounting platform to accommodate a multitude of optic requirements. The handguard system is free-floated, giving the owner superior performance and accuracy.

All complete rifles are assembled by our professional gunsmiths and are tested prior to leaving our facility. Buy with confidence when you purchase an Aero Precision Complete Rifle. Visit Aero Precision

Upper Features:

  • Upper: M5E1 Enhanced Upper Receiver in FDE Cerakote
  • Barrel: 16″ .308, Mid-Length, 1:10 Twist, 4150 Chrome Moly Vanadium, QPQ corrosion resistant finish
  • Handguard: Enhanced Series Handguard of choice
  • Gas System: Low Profile Gas Block and Mid-Length Gas Tube
  • Bolt Carrier Group: 8620 Steel, Phosphate Finish, Properly Staked, 7.62 Bolt
  • Muzzle Device: Standard A2 Flash Hider

Lower Features:

  • Lower: M5 Lower Receiver with tension screw and integrated trigger guard
  • Lower Parts Kit: Standard M5 .308 Lower Parts Kit
  • Buffer Kit: Standard Mil-Spec M5 .308 Buffer Kit
  • Stock: Magpul STR Stock
  • Grip: Magpul MOE Grip

Aero Precision M5E1 FDE 308AR

Genesis CNC

Genesis CNC 80% AR 308 Lower Receiver Pictured in a Drill Jig

Genesis CNC 80% AR 308 Lower Receiver Pictured in a Drill Jig

Genesis CNC – The Beginning for the AR-10 Rifle Builder:

The Right Balance of Power and Precision with Compatibility and Options


Right now our 80% .308 Lower Receivers are in stock and available to all customers at our discounted dealer pricing.
In Stock orders will be shipped within 24-48 hours of order placement.
Take advantage of this limited time offer!
Jig Assemblies will be shipping out starting early next week!

Genesis CNC is proud to offer our Gen-2 80% .308 Lower Receiver and .308 Stripped Upper Receiver which now provides the market with increased compatibility and options across the board.
The Genesis CNC .308 Upper and Lower Receiver pair is not only the foundation and starting point for the Rifle Builder, but also our parts allow current owners of LMT® / KAC™ / La Rue™ / Les Baer™/ Armalite™ .308 rifles to add another compatible Upper Receiver and build on their platform. Generally speaking, this has not been a readily available option.

Genesis CNC The Beginning for the AR-10 Rifle Builder

Genesis CNC


We have re-designed our Jig Assembly with dowel pins and a single base which is a far superior design to our previous model.

In the future we will be offering our jig with and without drill bushings with a cost reduction for jig assemblies without the drill bushings for the single user.

Genesis CNC 3


The Gen-2 80% Lower Receiver is not only compatible with LMT and KAC .308 Rifles, but also creates the option for current owners of Armalite™ .308 rifles to convert their rifles to accept PMAGs® and other SR series magazines.

Designed  to accept a DPMS™ Lower Parts Kits, with the exception of the rear take-down pin.

Generally, this design change not only creates significant cost savings for the customer but also the DPMS™ Lower Parts Kits are more readily available for purchase.


Genesis CNC

Genesis CNC


With our Gen-2 .308 Upper Receiver, current owners of high-end rifles such as LMT® / KAC™ / La Rue™ / Les Baer™ and Armalite™ now have the option to change the configuration of their rifle to meet their needs. Whether the shooter wishes to re-configure for competitive shooting, Hunting, or set up a Long Range Precision Rifle…without having to purchase a complete new rifle. The Genesis option provides a significant cost savings option for the individual.

Website: www.genesiscnc.com
Twitter: Follow Us @GenesisCNC
Instagram: For Up To Date Photos – Follow Us GENESIS.CNC
Facebook: Like Us on Facebook – 80% Lower Receiver
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Email: sales@genesiscnc.com




Wilson Combat 308 Super Sniper

Wilson Combat 308 Super Sniper

Wilson Combat 308 Super Sniper


Unmatched reliability meets pinpoint accuracy in the Wilson Combat .308 Super Sniper, the ultimate semi-automatic sharpshooting platform!

Wilson Combat’s legendary, match grade barrel– the heart of the rifle– elevates it among its contemporaries as the top choice of long range accuracy seekers. The barrel is precision button rifled from 416-R stainless steel, then chambered and reverse crowned for exceptional accuracy. The 1-10” twist chosen for the Super Sniper delivers consistent results all the way to 1000 yards with a broad range of bullet weights.

Our BILLet-AR machined aluminum upper and lower receivers have been designed and engineered to close tolerances. These allow for an ideal fit and a precisely bored bolt raceway for smooth operation.  Our exclusive Wilson Combat free-floating T.R.I.M rail is a comfortable and versatile handguard platform for mounting your favorite accessories.

The .308 Super Sniper is available with a fluted or non-fluted barrel, a 12” or 14” T.R.I.M  rail length, and your choice of Tactical Trigger Unit and Armor Tuff finish colors.


– 20” fluted barrel w/ 14” rail – Empty Weight = 9.2lbs, Loaded Weight = 10.7lbs, Collapsed Height = 37”, Extended Height = 40.25”

20” non-fluted barrel w/ 14” rail – Empty Weight = 9.5lbs, Loaded Weight = 11lbs, Collapsed Height = 37”, Extended Height = 40.25”

Christensen Arms CA-10 DMR 308AR

Christensen Arms CA-10 DMR 308AR

Christensen Arms CA-10 DMR 308AR

Christensen Arms CA-10 DMR 308AR

The CA-10 is the lightest AR-10 platform available on the market. A perfect match for precision shooting, tactical drills or hunting. Weight – 7.8 lbs. Standard Features

  • Christensen LTM Trigger
  • 1 MOA accuracy guarantee
  • Machined aircraft-grade aluminum receiver
  • Match-grade carbon wrapped barrel
  • Gas impingement operating system
  • Carbon-fiber hand guard with integrated carbon Picatinny rails
  • Nitride bolt carrier finish
  • Ambidextrous magazine release
  • Oversized bolt release
  • 20 MOA Picatinny receiver rail
  • Extended charging handle
  • Houge over-molded grip
  • OSS Banner flash suppressor
  • Accepts DPMS-style magazine
  • 1 MOA accuracy guarantee with appropriate ammunition
  • .308 Winchester chambering

Christensen Arms Optional Features

  • Hard black anodized Type III or Cerakote receiver colors
  • Camouflage dipping
  • Barrel length SBR to 24”
  • Titanium muzzle brake
  • Geissele, Timney or AR Gold trigger
  • Adjustable or fixed stocks
  • Ambidextrous safety
  • Numerous finish options
  • .243 Winchester or 6.5 Creedmore chambering

 Christensen Arms LOWER

  • Machined Billet 7075 T6
  • LTM Trigger System

Christensen Arms UPPER

  • Machined Billet 7075 T6
  • Integral picatinny rail

Christensen Arms BARREL

  • Carbon-Fiber wrapped
  • Match Grade
  • 1 MOA Guarantee
  • OSS Banner Flash Hider

Christensen Arms HANDGUARD

  • Carbon-Fiber
  • Intergral rails
  • Lightweight