Doug_M
04-09-2018, 06:16 AM
I've been doing a lot of reading trying to decide what optic to get. Probably going to buy used, perhaps new, and have it narrowed down to Aimpoint Pro, Eotech XPS2-0, or Trijicon MRO. The purpose is to replace irons on an AR for <100 shooting. I have a Leupold 3x9 on a QD mount for shooting groups. I've read lots of pro/cons for each one and am not looking to open up that can of worms here. Instead, I came across an extensive test of parallax that has disproven manufacturer claims of their optics being parallax free. Of course I would think most people take such a claim with a grain of salt, but as you will see below, perhaps those claims should have been taken with an entire salt shaker!
The test is extensive and as such cannot be posted here in its entirety so I recommend going to the link and at least skimming through it https://www.greeneyetactical.com/2017/07/27/comparative-study-of-red-dot-sight-parallax/
MANUFACTURER’S CLAIMS
One of the most significant aspects of the test is the comparison of the observed results, compared to the specific manufacturer’s claims as to the parallax characteristics of the optics. It should be noted that it is not made clear what aspect of parallax the manufacturer refers to in their product data. As parallax is defined as the apparent change of position of an object, viewed upon two different angles– it could refer to (in the case of this test) as to red dot movement or the actual target (viewing area) movement:
Aimpoint claims that the T-1 is a “1X (non-magnifying) parallax free optic” (Aimpoint, 2017), while the overall results showed an average deviation of 9.678492518 MOA from all distances and tests.
Aimpoint claims that the T-2 is a “1X (non-magnifying) parallax free optic” (Aimpoint, 2017), however, the average deviation observed across all distances and tests was 4.5 MOA.
Aimpoint claims that the Comp M2 is “Absence of parallax – No centering required” (Aimpoint, 2017), however, the average deviation observed across all distances and tests was 6.289849283 MOA.
Aimpoint lists no parallax claims on their website, that could be found at the time of publication, about the Comp M4 or the PRO.
Vortex claims that the StrikeFire II is “Parallax Free” (Vortex Optics, 2017), however, the average deviation observed across all distances and tests was 7.702254543 MOA.
Vortex claims that the Razor is “Parallax free” (Vortex Optics, 2017), however, the average deviation observed across all distances and tests was 15.59702284 MOA.
Trijicon claims the SRS is “PARALLAX-FREE” (Trijicon, 2017), however, the average deviation observed across all distances and tests was 16.26182102 MOA.
Trijicon claims the MRO is “PARALLAX-FREE” (Trijicon, 2017), however, the average deviation observed across all distances and tests was 13.37388861 MOA.
Leopold claims “The Leupold Carbine Optic (LCO) is parallax free” in an answer to the product questions (Service, 2017), however the average deviation observed across all distances and tests was 12.86041119 MOA.
EOTech claims that their optic is subject to parallax error of up to 14 MOA (EoTech, 2017). This claim is made generally on their FAQ page, without being model specific, however, the averages of the models tested across all distances and tests were: 1.658588792 MOA for the EXPS 3.2, 1.723615393 MOA for the EXPS 3.0, and 3.400581317 for the 516.
Burris claims that the Fast Fire 3 is “parallax free” (Burris Optics, 2017), however, users noted an average of 4.024137943 MOA of movement.
At the time of this testing, we could find no public claims by Primary Arms as to the parallax characteristics of the optic tested.
As we can see, there is a wide variance in what is claimed by the manufacturers and what is observed. All but Eotech, who over estimated error, failed to produce results that match the claims.
The test is extensive and as such cannot be posted here in its entirety so I recommend going to the link and at least skimming through it https://www.greeneyetactical.com/2017/07/27/comparative-study-of-red-dot-sight-parallax/
MANUFACTURER’S CLAIMS
One of the most significant aspects of the test is the comparison of the observed results, compared to the specific manufacturer’s claims as to the parallax characteristics of the optics. It should be noted that it is not made clear what aspect of parallax the manufacturer refers to in their product data. As parallax is defined as the apparent change of position of an object, viewed upon two different angles– it could refer to (in the case of this test) as to red dot movement or the actual target (viewing area) movement:
Aimpoint claims that the T-1 is a “1X (non-magnifying) parallax free optic” (Aimpoint, 2017), while the overall results showed an average deviation of 9.678492518 MOA from all distances and tests.
Aimpoint claims that the T-2 is a “1X (non-magnifying) parallax free optic” (Aimpoint, 2017), however, the average deviation observed across all distances and tests was 4.5 MOA.
Aimpoint claims that the Comp M2 is “Absence of parallax – No centering required” (Aimpoint, 2017), however, the average deviation observed across all distances and tests was 6.289849283 MOA.
Aimpoint lists no parallax claims on their website, that could be found at the time of publication, about the Comp M4 or the PRO.
Vortex claims that the StrikeFire II is “Parallax Free” (Vortex Optics, 2017), however, the average deviation observed across all distances and tests was 7.702254543 MOA.
Vortex claims that the Razor is “Parallax free” (Vortex Optics, 2017), however, the average deviation observed across all distances and tests was 15.59702284 MOA.
Trijicon claims the SRS is “PARALLAX-FREE” (Trijicon, 2017), however, the average deviation observed across all distances and tests was 16.26182102 MOA.
Trijicon claims the MRO is “PARALLAX-FREE” (Trijicon, 2017), however, the average deviation observed across all distances and tests was 13.37388861 MOA.
Leopold claims “The Leupold Carbine Optic (LCO) is parallax free” in an answer to the product questions (Service, 2017), however the average deviation observed across all distances and tests was 12.86041119 MOA.
EOTech claims that their optic is subject to parallax error of up to 14 MOA (EoTech, 2017). This claim is made generally on their FAQ page, without being model specific, however, the averages of the models tested across all distances and tests were: 1.658588792 MOA for the EXPS 3.2, 1.723615393 MOA for the EXPS 3.0, and 3.400581317 for the 516.
Burris claims that the Fast Fire 3 is “parallax free” (Burris Optics, 2017), however, users noted an average of 4.024137943 MOA of movement.
At the time of this testing, we could find no public claims by Primary Arms as to the parallax characteristics of the optic tested.
As we can see, there is a wide variance in what is claimed by the manufacturers and what is observed. All but Eotech, who over estimated error, failed to produce results that match the claims.