EOTech having problems with it's HWS

Coyotehunter_

Coyotehunter_

New member
I've recently read in other forums about the problem that the EOTech's HWS is having with zero shifts and some other problems.

http://soldiersystems.net/2015/09/30/uss...ts-plus-goings/

I've noticed that after storing my EXPS3-4 HWS in my non air conditioned attached garage that the zero has shifted.

My last two range trips using the EXPS3.4 has shown that it was not retaining it's zero.

I'm thinking that the Garage temperatures are going from extreme cold this past winter to hot this summer and that maybe the reason for the shift. I was off by 7" or 8" at the 200 yard range this past week. I thought at first that I had put the HWS on the picatinny Rail improperly but after checking this I found that it was on the rail properly and it the right spot.

I've recently read that extreme temperature changes can have an ADVERSE effect on the EOTech's HWS zero point.

Since I been taking a lot about the EOTech system in the past I thought it would be appropriate for me to give you all this information that I found just in the last few days.

NOTE: in the past I stored the unit inside the house where it was a more constant 75 deg F and never had this shift in Zero problem. I also normally go shooting when the temperatures are nice. I avoid extreme cold weather and extremely hot weather. I mostly shoot when the weather is nice and calm and around 75 to 85 deg. If it's 100 deg F outside I'm normally inside in the AC. And if it's 50 deg F or lower I'm either in the house or dressed like a polar bear if out hunting. The EXPS system is transported to the hunting site inside the heated truck in the winter months when I hunt.

Now at the 25 yard range the POI zero didn't seem to be off. Actually I had not shot the gun at the 25 yard ranges since zeroing in the EOTech. I did that at the 50 and 200 yard ranges. I only went to the 25 yard range the other day to see what the system would do at closer ranges. And at 25 yard the EOTech and the Ambush Firearms together put three bullet holes touching each other in the 2" bulls eye. They were low and to the right but inside the 2" diameter Orange bulls eye on the 17" diameter Shoot N C target.

Note: L3/EOTech have removed the reference to the temperature range of these HWS in their online manuals. But my original manual should still have the temperature ranges that the unit was designed to work within. And they also changed the online manual for the EXPS3 systems to say that the elevation and windage knobs adjust to (APPROXIMATELY)0.5 MOA. Where before it said 0.5 MOA. They have added the word "approximately" to the manual for some reason. They also have said in a report to the government SEC that they may have a 26 million dollar problem. Could that problem be the company have to buy back all the systems that the sold to the Government and to the public as well as the systems have failed to perform as they were suppose to?

I bought this system thinking that if the Military guys were using it is must be great. But if the zero can change by 4 MOA with the temperature changes that not what I want to hear after buying the unit.

I'm thinking about calling EOTech and asking for a refund or a new unit since they only warranty these $500 dollar units for two years.

NOTE: This information that being reported has been developed at the Crane Naval Facility in INDIANA. These guys are located in my state and they do all kinds of research on weapons so I trust them with this information. If the guys at Crane say it's not right then I believe them. Also the Special Operations Units have been issued a warning about this zero shift with extreme temperature changes.

And now I'm hearing about Parallax errors with these HWS. What else can go wrong?

Since I prefer to hunt and shoot in ideal weather conditions I didn't notice this problem until now. If I hunted in extreme weather conditions more often I would have probably noticed this problem much sooner.
 
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Any specific suggestions on how you would do that if you were me? I'm all ears.

I do plan on calling L3 tomorrow and discussing this with them if they will listen and help me that would be cool. If not then want do I do? Join in any class action law suits and try to recover my money? After this is released I doubt anyone will be wanting to buy the EOTech anymore.

This is all coming from reports that Crane Naval Base in Indiana has found two issues with these EOTech HWS. Both are temperature related problems with the Zero and the Parallax shift in POI or zero. I'm troubled by this.

http://soldiersystems.net/2015/09/30/uss...ts-plus-goings/
 
Coyote,

I have been using the Eotech EXPS3-0 for several years hunting hogs. I mostly used them at night with a Gen3 PVS14 and 3x magnifier behind the unit or with a FLIR T70 thermal in front. For day hunting I would use either a 3x or 4x magnifier behind the unit.

I never had any shift issues and the units always provided me with a very versatile optic for day and night use. With regard to temperature there was never anything overly extreme so I can't offer an opinion on that. (25 to 95 degrees where I live) The only other variable I can imagine that might affect the unit is if it was slid forward and mounted securely and if there were good reliable lithium batteries in the unit.

When sighting the units in I assumed there was some slop in the .5 MOA adjustment because the screws turn and do not seem to click into a slot. I just turned until I had my Zero and left it at that. Also, I would always turn past the point I wanted and then back a little so the screw would settle into that position.

I also know that if you have any astigmatism issues you will have problems with this sight. I have a slight problem with it and noticed a sort of double spot for the middle dot especially at brighter settings. I had to dial the unit way down and shoot to determine which one would give me the correct POI. Once I adjusted it was not a problem and the unit proved to be a reliable optic for hogs.

I know some guys cannot use the Eotech at all because of astigmatism issues and it also seems to be worse without some type of magnifier behind the unit. You may want to ask your eye doctor about it next time you go for an eye exam just so you will know.

It appears that you have done your homework so it will be interesting to see where this goes. I have 2 of the units and I am selling one of them because I have switched to thermal. I am confident enough to keep one for an AR unless something is issued by L3 about a problem with the unit.

Hey....at least you can have fun shopping for a new scope.

FYI.... you are in good company.....between the 2 units and magnifiers and mounts I have about $2k tied up in these units.
 
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I will be seeing the eye doctor in Jan of 2016. I had three eye operations in the last year and have to wait until then to get fitted with corrective eye glasses. I had the Laser assisted cataract surgery to help get rid of cataracts in my natural lens in my eyes and then also have the Eye Surgeon correct my astigmatism in both eye. However he didn't do a perfect job as I still have some astigmatism left. At times I still see double letters on the TV screen. However I've not noticed the astigmatism as much when I use the EXPS3-4 with the G33 magnifier. Which is a good thing. I use to wear thick eye glasses and don't need them anymore to see things far away. I now have to wear reading glasses to see the computer screen and to read books etc.

I never had this zero shifting problems the first year that I owned the EOTech system. That's because I keep it inside the house all the time and only went to the rifle range to use it in nice 70 deg weather. So the Zero was right on the money when I put the EOTech back on the rail.

This past winter and this past summer I stored the EOTech out in my un conditioned and uninsulated attached garage and it was exposed to high and low temperatures while in the garage for the last 10 months or so. Only then did I noticed the zero being 8 " higher than before. I corrected this and was able to shoot some more and hit the bulls eyes a few times before the range closed. I need more range time to figure this all out.
 
Originally Posted By: Coyotehunter_I never had this zero shifting problems the first year that I owned the EOTech system. That's because I keep it inside the house all the time and only went to the rifle range to use it in nice 70 deg weather. So the Zero was right on the money when I put the EOTech back on the rail.

This could be at least part of the problem. I can tell you from experience that even though the unit has a QD mount that good POI repeatability is not there. I always had to mount my units and adjust after shooting to make sure the units were seated tight on the rail. I almost always had to cinch down the unit again after shooting some.

One other thing might be your battery. You did not say anything about it but it's not a good idea to store anything long term with a lithium battery installed. If you are going to try to work with the unit I would put a new high quality battery in it and start fresh.

 
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I'm responding to your comments about my eye's astigmatism problems. I'm not sure if you made this post before or after I had my eye operations to correct for my astigmatism or not. The astigmatism is corrected for the most part but there are times at night when my eyes are tired that the astigmatism raises it's ugly head again when I'm watching TV. The eye surgeon tried to use a laser to fixe the astigmatism in my left eye and my right eye. He had to so some more work in my right eye as the laser work didn't do the job full. He did some new cuts on the cornea of my right eye while I was in his office. He just gave me some numbing eye drops in my right eye and used a scalpel to make some deeper cuts in my cornea. I suspect he could see the few day old cuts that the laser beam did on my eye and just followed them. He was wearing these headset magnifiers to see my eyes while he used the scapel to deepen the incisions. This did help better correct most all my astigmatism problem in my right eye. I had a left eye retinal problem making it hard for me to tell if he got ride of all the astigmatism in my left eye. As my left eye's retina heals and I can see better I'm noticing some astigmatism in the left eye as well. I won't see the cataract eye surgeon again unless I make an effort to contact him and tell him the problem. But I need to wait until next month when I see my Retina Surgeon and find out how my left eye's retina is healing. I had the retinal surgery done at another eye surgeon. Each Doctor specialized in different procedures so I had to have two different surgeons for my eye operations. I'll talk to Dr. Summerville next month and see what he says. And if the retina is healed up fully then I'll make contact with the other eye surgeon and ask him to see what he suggests. I'm fearful that he may not want to address this issue. I know that insurance pays about $3000 per each eye to have cataract surgery. And I paid him $1,200 extra for each eye to use the Laser system which was also suppose to fix the astigmatism problems in both my eye while also taking the cataracts out of both my eye and putting in new inner ocular lens. So right now when my eyes are rested I can see the EOTech 1 MOA red dot's a lot better. I use the G33 magnifier with the EXPS3-4 HWS and I'm not having the problem seeing the red dots like I did before the operations. I'm lucky to still have good vision in my left eye. I can see 20/20 in both eyes now. But I have another problem that neither of my eye surgeons have really addressed. It's called :

http://www.opticaldiagnostics.com/info/aniseikonia.html

And neither of my eye surgeons will talk about this to me at any length. They both said that they will correct this problem when they take out the old lens in my eyes and or repair the epiretinal membrane on my left eye's retina. But the Aniseikonia is still there and my left eye sees things twice as large as my right eye. This making focusing both eyes together on the same object problematic. But each eye can read the eye chart on the 20/20 line. But the left eye's vision is not as clear as the right eye even though I can make out the letters on the 20/20 line of the eye chart. But the good news is that I'm now LEFT eye dominate and can shoot better. I use to be left eye dominate and had to close my left eye to shoot well. But that's no longer a problem as my brain disregards the left eys's vision and use the right eye now. Funny how the brain works like that. But the right eye' vision is so much better although smaller than the left eyes vision.

I'm thinking that my left eye is getting better now. It's been almost a year since I had the retina operation last December 2014. And it takes from 6 months to 1 year for the retina to heal from such a delicate operation. The eye surgeon had to peel a 5 micron thick layer of tissue off the front of my retina in order for me to see again. And if he didn't get all the epiretinal membrane off my retina then the parts that are left can disform the retina and make vision problems. I use to see horizontal lines as wavy lines instead of straight lines and that's been fixed. But vertical lines still seem to be bent. So for example if I'm driving down the road and look out at the telephone polls along the road I see the tops of the polls as being bent over a little bit instead of perfectly straight up and down like they are suppose to be. That tells me that my retina is still swollen a bit and not seeing perfectly like it should. And then there is the astigmatism problem that's still there in my left eye. I' get that fixed somehow in the future if possible.
Originally Posted By: Gman757Coyote,

I have been using the Eotech EXPS3-0 for several years hunting hogs. I mostly used them at night with a Gen3 PVS14 and 3x magnifier behind the unit or with a FLIR T70 thermal in front. For day hunting I would use either a 3x or 4x magnifier behind the unit.

I never had any shift issues and the units always provided me with a very versatile optic for day and night use. With regard to temperature there was never anything overly extreme so I can't offer an opinion on that. (25 to 95 degrees where I live) The only other variable I can imagine that might affect the unit is if it was slid forward and mounted securely and if there were good reliable lithium batteries in the unit.

When sighting the units in I assumed there was some slop in the .5 MOA adjustment because the screws turn and do not seem to click into a slot. I just turned until I had my Zero and left it at that. Also, I would always turn past the point I wanted and then back a little so the screw would settle into that position.

I also know that if you have any astigmatism issues you will have problems with this sight. I have a slight problem with it and noticed a sort of double spot for the middle dot especially at brighter settings. I had to dial the unit way down and shoot to determine which one would give me the correct POI. Once I adjusted it was not a problem and the unit proved to be a reliable optic for hogs.

I know some guys cannot use the Eotech at all because of astigmatism issues and it also seems to be worse without some type of magnifier behind the unit. You may want to ask your eye doctor about it next time you go for an eye exam just so you will know.

It appears that you have done your homework so it will be interesting to see where this goes. I have 2 of the units and I am selling one of them because I have switched to thermal. I am confident enough to keep one for an AR unless something is issued by L3 about a problem with the unit.

Hey....at least you can have fun shopping for a new scope.

FYI.... you are in good company.....between the 2 units and magnifiers and mounts I have about $2k tied up in these units.
 


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