AR Sponsor
Posted: 5/23/2004 1:12:04 PM EDT
| Are they parallax free? |
|
No. At the edges of the window, there is some horizontal parallax. This has been confirmed by several folks here, and can easily be seen by placing the rifle on a rest with the reticle on a target, and then moving side to side. As the reticle approaches the edge of the window, it will begin to move off-target. I understand that it's supposed to have little or no vertical parallax, but given the ballistic trajectory, parallax in that direction is less important anyway. The only reflex-type optic that I know is parallax-free is the AimPoint, due to the complex lens design it has. -Troy |
|
Actually, the Aimpoint also has some parallax issues at closer ranges. The parallax issue that Troy is talking about only happens if you move the outer ring of the EOTech reticle off the sight pane. As long as the entire reticle is in the sight pane there are no issues. I also wanted to mention that no optic is completely parallax free at all distances. This is not a fault of the optic but rather just the the nature of the beast. Some optics companies may claim to be "Parallax Free" but if you read the details in the specs they will all list parallax error stats. I believe there was also a previous thread that listed the parallax error data for both the Aimpoint and the EOTech, If we're lucky maybe someone can post a link to it. 
|
That is correct. The Aimpoint is NOT Parallax free (out to around 25yds)... C4 |
|
SMGLEE told me that his testing confirmed that the EO tech was paralax free, as long as the entire 65MOA ring was inside the window. only when the 65MOA ring left the window, did the sight exhibit slight POI changes (slight for close range, is more of a problem further out.) But up close is probably trhe only place you will need the sight so quick that you shoulder the rifle and don't find that 65MOA ring inside the window. (if you are setting up for a long range shot and it is outside the window, you are a dumbass.) Not a problem, I have never noticed it. I can shoot 1 inch groups standing offhand at 25meters with my EO tech on an M4 FF RAS MRE upper. My results aren't as good with Aimpoints (I think it is the bigger dot, and depending on the sight it can be pretty hairy, I preffer the 1moa EO dot. I saw an article about a US Army sniper in Iraq using an EO-Tech to get 8 confirmed kills (I think they were inside 300meters, but I'm not sure), and I guess if it is good enough for him, it is good enough for me. |
|
It is correct that NO optic can be parallax-free at very close range, simply because of physics. But at close ranges, you generally don't need that level of precision anyway. I wouldn't pass on an EOTech due to its parallax issues, because as pointed out, they are minor, and predictable (and therefore avoidable). Most other reflex-type optics are noticably worse. -Troy |
|
I ran a 5 day class for a 15 man tactical team issued brand new select fire Colt M4's with Eotech 551's. During the sighting in of the 551's, each shooter was made to fire 5 shot groups from 3 yards to 100 yards to become familiar with the particular weapons trajectory at each of the distances. Almost all of the shooters noticed that from the 25 yard line and closer that the 5 shot groups were very tight, but would deviate sometimes up to 2 inches when the shooter re-positioned his cheek weld for the next 5 shot group. If the shooter kept the dot centered at the top of the front sight post, the deviation diminished. At the 50 yard line out to 100 yards, no deviation was noted |
AR Sponsor