I am thinking about making the change from my Aimpoint M2 to a EO TECH 552. At the gun shop we mounted the EO TECH on a flat top and for some reason or another the sight looked canted on the rifle (looking from the rear forward). We took that EO TECH off and replace that sight with another. The other sight looked the same (canted). Is this normal?

No, it is generally because the angle of the flattop upper is off; not the EO Tech.

It is the same on my Oly upper, but they offered to take it back and send me a new one.  I declined, as it is not worth the hassle - doesn't affect me operationally at all.

Had my new Eotech mounted on my Colt LE6920 flat top for the past week while waiting for my RRA Dominator mount to come in. No problems with canting.

The RRA Dominator came in today and I placed my Eotech on it without any canting. Lines up perfectly.

Quoted: We have some of the 552 in stock with out this problem and we have a special on the 552! Mike @ CSGW www.csgunworks.com [email protected] Here’s some testimonials about CS GunWorks for AR15 Board What do YOU have to say about CS GunWorks

Nice try mike

Did it look like mine?  Here are some pictures of my FINE EOTech!



It leans on every rifle that it is put on.  It leans on my upper, my Troy MRF-C also, but EOTech says that the sight is fine and ALL the rifles receivers are out of spec!  My suggestion, keep your Aimpoint, that is what I should have done from the beginning and just as soon as I am able, this thing is being replaced with an M3.

I have got revise my post from above. It would appear that I was wrong and that my EOTech does cant to the left after all.

I just got around to taking some pictures and noticed that it was canting to the left when I was taking a picture from the front.

I included the picture that best shows it. The picture does not focus on the EOTech, but you can see it.

Does anyone know if this will effect accuracy, if not I'm not going to worry about it or should I contact EOTech ?

Mine cants a little to the right, but nowhere NEAR that much.

However, it didn't cant at all when I put it on about 6 of my buddy's uppers......So I discerned it was my Oly upper being off.

Mine shoots fine, it is just annoying as hell to look through it and use the irons.  Thumbs up to EOTech for some good quality control!  

1. Before you go blaming EOTech for quality control issues for canted sights, get out a micrometer and measure your rail. Not just the width, but the angles of the sides.  They need to be 45 degree angles to be a true Mil Spec Picatinny rail.  I've seen many out of spec 1913 Picatinny rails on receivers and mounts from various manufacturers.  I've yet to see an out of spec EOTech.

2. If your rail is in fact in spec, then contact EOTech customer service for a replacement sight.

I bet that if you do number 1, you won't need to do number 2.

Quoted: Quoted: 1. Before you go blaming EOTech for quality control issues for canted sights, get out a micrometer and measure your rail. Not just the width, but the angles of the sides.  They need to be 45 degree angles to be a true Mil Spec Picatinny rail.  I've seen many out of spec 1913 Picatinny rails on receivers and mounts from various manufacturers.  I've yet to see an out of spec EOTech. 2. If your rail is in fact in spec, then contact EOTech customer service for a replacement sight. I bet that if you do number 1, you won't need to do number 2. I guess you did not read what I wrote above. I purchased a Jan 2005 producted 552 in March. It sat canted on my Colt, KAC, Bushies, RRA, Oly, two CMTs, and two no name uppers. I called EOTech in May or June to ask them about it. They sent a replacement. Guess what, the new unit did not cant on any of my rifles or uppers. I have since purchased another EOTech a 551 and it does not sit canted either. EOTech had a bad run of mounts end of story.

Well, the replacement that they sent me also canted.  That is why I am saying, if their quality control is that bad, I won't buy another sight from them and I will discourage anyone from buying their sights.  

You're in a trick bag.  When you buy the sight fro the distributor, they say that the sights are not returnable if it has been mounted on a weapon.  How do you know if these sights are going to sit right on you're weapon until you mount it?  So after it's mounted, you're screwed and then EOTech just blames your rifle and says that it is out of spec.  I would put my 511 on any rifle and bet that it sits canted.  It sits that canted on my receiver, on my Troy rail, on my YHM EOTech riser and it leans the opposite direction when it is mounted backwards on my reciever.  It is not my rifle, it's the POS sight!

Ok, here is the situation in immense detail regarding our sights sitting canted (or any other accessory that attaches to a MIL-STD-1913 rail).

We did not have a bad run of bases and our quality control is second to none. As of 11/30/05 we have manufactured 208,054 sights since Jan 1, 2001. Of all of them, we have had 4,020 returned for repair (any type of repair, including cants). That is 1.9%. That's good.

Better yet, in 2005 we have produced 70,199 sights so far. We have had 132 returned for repair. That is 0.18%. From a manufacturing standpoint, that is impressive. This is due to a series of more stingent quality control measures put into place approximately 1.5 to 2 years ago.

However, all of that is irrelevant, as niether our return rate nor the impressive success of our quality control has anything to do with sights sitting canted, and here is why:

Please do a search for the MIL-STD-1913 rail Federal Publication from 3 Feb 1995. Near the end of the document are engineering schematics with the "precise" dimensions of the accessory or picatinny rail. You will notice that there is a range of allowable measurement for the thickness of the rail, height, and width. The range for the width of the rail alone allows for a possible difference in inches of over EIGHT TENTHS (0.8). That is not a small allowance when it comes to interfacing products. The height of the rail allows for a variance of .14 inches! The impact this has, is that if you produce something to fit a tight or specific tolerance (one exact measurement), you will only fit on the few rifles that meet that specification (less sales, less profit, less money to be spent on quality control...). Additionally, the amount of scrap that would be produced by rifle manufacturers due to not meeting that specification would make the industry completely not-profitable, and you'd be paying $4,000 for a new M4 as opposed to $900 (as an example).

Consequently, we manufacture a base to meet the tolerance of the greatest measurement allowed in the spec. This ensures that we fit on all rails. The design of the base allows for 3 tangential contact points to guarantee a secure fit and consistent zeroability. However, if your rail is one that has a different variance or is compeltely out of spec, it can result in our sight appearing canted on the rail. You can put the sight on 20 different rifles, and unless they are all the exact same in measurement, the sight may vary in its flushness on the different rifles. You'll notice that the cant changed as you moved it from rifle to rifle and in different slots on the same rail. Also, be aware that the cant is purely aesthetic and does not impact the operation or effectiveness of the sight.

A way to examine the effect of this is to go back to the top of this post and look at the percentages of return. It is not a common occurance. During the manufacturing AND the QC process the sight is constantly mounted on 1913 rails. They sit flat. If they were to sit canted, the effect would be obvious due to magnified systems that inflate the reticle images to great detail during inspections.

This range in tolerance of the rail affects all accessories, not just our sights.

Above all of this, I would like nothing more that to find out our sight is in error. This would allow me to fix the problem (if it were attributed to the sight). I make it a practice to get the canted sights in and examine them to ensure that it is not our base. Of the 18 that have been turned in this year, NONE have been out of spec. Not only within the variance, but none have been out of the single tolerance our extruded aluminum bases are produced to. I'd like to tell you otherwise, but I can't. We go to great lengths to keep our customers satisfied and meet their needs (even replacing sights, though it doesn't solve the problem).

If you would like to discuss this directly, please feel free to call me. (734)741-8868 x3919

Good post - may I quote you on another site?

Thanks for the reply.  I will accept your answer as truth as I have EOTech products and are completly satisified with them all.  

I am going to use mine as is. For me the sight works great and improves my accuracy. I can get use the canting and it is probably the fault of my rifle.

Like Dennis says, it is just a matter of aesthetics and does not impact the operation or effectiveness of the sight.

It does what I need it to do and and that's what counts for me.

Quoted: Well, the replacement that they sent me also canted.  That is why I am saying, if their quality control is that bad, I won't buy another sight from them and I will discourage anyone from buying their sights.   You're in a trick bag.  When you buy the sight fro the distributor, they say that the sights are not returnable if it has been mounted on a weapon.  How do you know if these sights are going to sit right on you're weapon until you mount it?  So after it's mounted, you're screwed and then EOTech just blames your rifle and says that it is out of spec.  I would put my 511 on any rifle and bet that it sits canted.  It sits that canted on my receiver, on my Troy rail, on my YHM EOTech riser and it leans the opposite direction when it is mounted backwards on my reciever.  It is not my rifle, it's the POS sight!

I've had a number of EOTech sights.  I've had them cant on one receiver and on a couple of  mounts, even an ARMS SWAN Sleeve - From the company that invented the spec!  I downloaded a document that shows the dimensions on the Picatinny rails and I measured all my rails.  In every case where the sight canted the rails were out of spec. When I mount the EOTech on a rail in spec, no cant.  Hmmm.   I read what you're saying above, but; did you actually measure your receiver rail and compare it to spec before blaming the sight?  Because both of your sights canted on the same rail, I would think that would indicate the rail is probably at fault rather than both sights being bad.  
I can email you a pdf containing the specs on the 1913 Picatinny rail if you would like and you can compare your rail to the actual spec.  Let me know.  -Manx

Wow, great post Dennis!

Seeing the those numbers really gives a better perspective of how reliable the EOTech sights have been!

I'd also like to quote those numbers if it's okay with you.

I don't buy it.  If my rifle's receiver is so out of spec, then why would I have not been able to notice this with my carry handle mounted?  I mean, you can see how far it leans, the carry handle would have leaned that far also, which it didn't.  Good grief, I hardly would have been able to sight down the handle!  Also, if the sight is fine, then why when I mount it on the rfle backwards does it lean the opposite direction?  Is the rail flexible?  I wish I had a really good quality digital camera, with the 511 mounted, you can see the gap on the right side when it is leaning over to the left, I just don't buy that it's the receiver.  

Also, why didn't my Trijicon Reflex NSN sit tilt on the receiver then?  It had a lot smaller window and I know that I would have noticed if it was tilted when I sighted through it.

Like I have said before, this is the last EOTech that I will purchase and I will replace it as soon as I am able.  I just love showing this sight to other officers when they ask about it.  I hand the rifle to them and ask them what they notice about it and their response is, "Oh my!"  Then I tell them not to buy an EOTeh and buy an Aimpoint.  

Yeah, it doesn't effect the way the sight works, but it is as annoying as hell to sight through it with your irons when it leans that much.  If it was just a little bit, I wouldn't mind, but this is pittiful.


EDIT:  Oh, and I don't expect anyone to believe that the sight is faulty, I am sure that it is all just me.  Everyone on this board talks about the Colt "cool aid" drinkers, well, I can tell you that the EOTech "cool aid" drinkers are far worse than anyone else.  I'm sure Rolls Royce produces and product that is not up to par once in a great while, they are probably just decent enough to admit it.

Rolls Royce Recalls

Rolls Royce Recalls 2


See, even Rolls admits that they make a faulty product once in a while.  Sounds like EOTech is REALLY on the leading edge of the production industry since they haven't produced a bad product yet.  

Maybe they should expand their services to other companies (such as Rolls) to help them with their quality control.

Quoted: Quoted: Like I have said before, this is the last EOTech that I will purchase and I will replace it as soon as I am able. I just love showing this sight to other officers when they ask about it.  I hand the rifle to them and ask them what they notice about it and their response is, "Oh my!"  Then I tell them not to buy an EOTeh and buy an Aimpoint.   Please let me know how much you want for your optic. I would love to buy it from you. I am simply tired of reading your posts about your problem EOTech. I will make the head ache go away, just let me know how much you want.

Why should you have to buy a POS that EOTech put out?  I'm the one that is stuck with it.  That's the thing, who is going to want to buy a POS sight that doesn't even sit true on their rifle?  I would have to sell a $300.00 sight for far less than what I paid for it when it is only a couple of months old and practically and take a loss.  Then I would have to come up with the extra few hundred dollars for an Aimpoint and mount, which I can't do this time of year.  It just wasn' too much to ask for, to ask that your sight sit square on your rifle.

But, I guess if you are tired of reading my posts, then skip over them because I am going to post pictures and explain to everyone about my POS sight every time I see a thread started with someone asking about an EOTech, just like I do in the field.  Besides, this is what this websight is for, to discuss AR15 products GOOD AND BAD and let people know the potential problems and let them determine if they want to buy that particular product.  I'm sure going to let people know if they buy an EOTech, they are taking a gamble of being stuck with a $300.00 lump of crap on top of their rifle!

To all: Anything I post on a public forum is quotable. Have at it.

INTrooper425:

The first indication that the problem wasn't the sight was when the replacement (and that's the replacement sight that we sent to you free of charge along with a prepaid shipping label to send back the other one) sat canted as well. I am curious if there was a change in the degree of cant as you moved the sight between rifles; another indication that it is a rail specification issue. If you are so adamant about speaking negatively about our product, I'd like to see it backed up with some statistical info (i.e. maybe some rail measurements, etc.).


I don't buy it. If my rifle's receiver is so out of spec, then why would I have not been able to notice this with my carry handle mounted? I mean, you can see how far it leans, the carry handle would have leaned that far also, which it didn't. Good grief, I hardly would have been able to sight down the handle

The engineering drawings and measurement variances for the 1913 rail are a fact. I can't help convince you of their existence. They just are.

The carry handle fits flat as it is made to the same measurements becaue it is made by the same manufacturer. The sight leans in the opposite direction because you're turning it around. The mouting interface is now reversed and the tangential contact points are contacting on the opposite sides.

Here is a quote from our original correspondence via email back in November:

"There is no one out there who would like to find a base of ours out of tolerance more than me. I offer to replace every sight for the customer so I can get theirs back in, in order to chop theirs up and prove our engineers are dropping the ball. My number one priority is to be the advocate of the customer. I love to find these problems and correct them...We stand behind our product 100% and my offer to replace your sight is available if you change your mind. We have had our shares of failures and always used them to develop and make our product better. I would like to say that we have found defects in our rail, but we haven’t. I will continue to treat each instance as the one that could be, but to this point it is true that we have not turned up a bad product (that quote in context refers specifically to the canting issue)."

Same type of statement as I made in an earlier post. I am more than happy to admit fault, in fact it is part of my job. I am glad Rolls Royce does it as well. We have been very open about product failures and quality levels throughout our history. For example, I am sure if you go through some of the archives on this sight you'll find discussions about zeroing issues we used to have. Guess what? We admitted it in addition to correcting the problem (both internally and for the consumer). Our current position within the DOD, Fed LE, and Domestic LE would be a pretty good indication that our production process and QC is doing its job.

If you show me that there is not a variance between rails of rifle manufacturers, and that every rail is the same, and that all your rifles are that exact measurement, I'll buy back your sight(personally). Seriously, I will send you a check for the sight and take it back. There better be proof, as I have provided it to the contrary. If you continue to simply say that you don't believe me or what I am saying (despite it being based on documentation), then I don't think there's any resolution to this. I guess you'll just continue to make statements about our manufacturing process and our products that you have no legitimate evidence to support.

Quoted: To all: Anything I post on a public forum is quotable. Have at it. INTrooper425: The first indication that the problem wasn't the sight was when the replacement (and that's the replacement sight that we sent to you free of charge along with a prepaid shipping label to send back the other one) sat canted as well. I am curious if there was a change in the degree of cant as you moved the sight between rifles; another indication that it is a rail specification issue. If you are so adamant about speaking negatively about our product, I'd like to see it backed up with some statistical info (i.e. maybe some rail measurements, etc.). I don't buy it. If my rifle's receiver is so out of spec, then why would I have not been able to notice this with my carry handle mounted? I mean, you can see how far it leans, the carry handle would have leaned that far also, which it didn't. Good grief, I hardly would have been able to sight down the handle The engineering drawings and measurement variances for the 1913 rail are a fact. I can't help convince you of their existence. They just are. The carry handle fits flat as it is made to the same measurements becaue it is made by the same manufacturer. The sight leans in the opposite direction because you're turning it around. The mouting interface is now reversed and the tangential contact points are contacting on the opposite sides. Here is a quote from our original correspondence via email back in November: "There is no one out there who would like to find a base of ours out of tolerance more than me. I offer to replace every sight for the customer so I can get theirs back in, in order to chop theirs up and prove our engineers are dropping the ball. My number one priority is to be the advocate of the customer. I love to find these problems and correct them...We stand behind our product 100% and my offer to replace your sight is available if you change your mind. We have had our shares of failures and always used them to develop and make our product better. I would like to say that we have found defects in our rail, but we haven’t. I will continue to treat each instance as the one that could be, but to this point it is true that we have not turned up a bad product (that quote in context refers specifically to the canting issue)." Same type of statement as I made in an earlier post. I am more than happy to admit fault, in fact it is part of my job. I am glad Rolls Royce does it as well. We have been very open about product failures and quality levels throughout our history. For example, I am sure if you go through some of the archives on this sight you'll find discussions about zeroing issues we used to have. Guess what? We admitted it in addition to correcting the problem (both internally and for the consumer). Our current position within the DOD, Fed LE, and Domestic LE would be a pretty good indication that our production process and QC is doing its job. If you show me that there is not a variance between rails of rifle manufacturers, and that every rail is the same, and that all your rifles are that exact measurement, I'll buy back your sight(personally). Seriously, I will send you a check for the sight and take it back. There better be proof, as I have provided it to the contrary. If you continue to simply say that you don't believe me or what I am saying (despite it being based on documentation), then I don't think there's any resolution to this. I guess you'll just continue to make statements about our manufacturing process and our products that you have no legitimate evidence to support.

Yep, you did send me another sight, that did sit canted, although not quite as bad.  Why would I replace my sight with ANOTHER canted sight and waste the ammo sighting it in?  I'm not complaining about the customer service, if you do a search, I actually complimented you on your customer service, I just DO NOT LIKE YOUR PRODUCT for the above reasons.  When I placed my sight on another officer's Rock River, it DID sit exactly like it does on mine, we even mounted my rear sight on as well to check the alignment and it was the same. Also, did I not offer to reimburse you for the shipping?  Yes, I did, so don't try to make this out as I am the bad guy.  I also have that email if I need to refresh your memory.  

As far as getting specs off of my receiver, I'm not an engineer, I have no idea what I am doing as far as taking the specs or I would.  I guess this situation will not be resolved, I will believe what I believe and you will contiue to tell everyone that their receivers are out of spec.  Oh well, I am the one that is stuck with the crap sight and fine, but don't expect me to be bragging to others about your product.  

If you look back up to the middle of this thread, Boom posted tha the had a canted sight.  His was replaced and his replacement sat true.  So, I guess his receiver wasn't out of spec, must have been his sight.

EDIT:  Again, if my receiver is so out of spec, then why did my Reflex not sit canted as does your 511?  It is not made by Colt as you explained with my carry handle, so it should lean also, right?  Well, it didn't.

EDIT: Again, if my receiver is so out of spec, then why did my Reflex not sit canted as does your 511? It is not made by Colt as you explained with my carry handle, so it should lean also, right? Well, it didn't.

I didn't think the reflex mounted the same way, so its an apples and oranges if you are gauging the receiver as it spec or not.

Quoted: EDIT: Again, if my receiver is so out of spec, then why did my Reflex not sit canted as does your 511? It is not made by Colt as you explained with my carry handle, so it should lean also, right? Well, it didn't. I didn't think the reflex mounted the same way, so its an apples and oranges if you are gauging the receiver as it spec or not.

It's all mounting hardware for the 1913 rail, so it should be "apples and oranges" at all.

Quoted: I don't buy it.  If my rifle's receiver is so out of spec, then why would I have not been able to notice this with my carry handle mounted?  I mean, you can see how far it leans, the carry handle would have leaned that far also, which it didn't.  Good grief, I hardly would have been able to sight down the handle!  Also, if the sight is fine, then why when I mount it on the rfle backwards does it lean the opposite direction?  Is the rail flexible?  I wish I had a really good quality digital camera, with the 511 mounted, you can see the gap on the right side when it is leaning over to the left, I just don't buy that it's the receiver.   Also, why didn't my Trijicon Reflex NSN sit tilt on the receiver then?  It had a lot smaller window and I know that I would have noticed if it was tilted when I sighted through it. Like I have said before, this is the last EOTech that I will purchase and I will replace it as soon as I am able.  I just love showing this sight to other officers when they ask about it.  I hand the rifle to them and ask them what they notice about it and their response is, "Oh my!"  Then I tell them not to buy an EOTeh and buy an Aimpoint.   Yeah, it doesn't effect the way the sight works, but it is as annoying as hell to sight through it with your irons when it leans that much.  If it was just a little bit, I wouldn't mind, but this is pittiful. EDIT:  Oh, and I don't expect anyone to believe that the sight is faulty, I am sure that it is all just me.  Everyone on this board talks about the Colt "cool aid" drinkers, well, I can tell you that the EOTech "cool aid" drinkers are far worse than anyone else.  I'm sure Rolls Royce produces and product that is not up to par once in a great while, they are probably just decent enough to admit it.

Are you as much as of douche that you cannot accept that you neither them or you are wrong.  Both of them are made "In Spec" however with the variance’s he is talking about (on the upper receiver) will allow for a cant... end of story...  There was a long thread about this on a Troy BUIS cant Issue and Troy said the same thing to their customers...

Q :Well this effect your Point of aim point of impact ...  ?

A:  NO

Its simply cosmetic... Keep on thing in mind, these, along with any another part for these rifles are made for one think.. Killing... and Whacking Tangos... and protecting life’s of those you care about !! If you focus on the small stuff like this... You need to find yourself another job.. or hobby if you choose !

Quoted: Quoted: I don't buy it.  If my rifle's receiver is so out of spec, then why would I have not been able to notice this with my carry handle mounted?  I mean, you can see how far it leans, the carry handle would have leaned that far also, which it didn't.  Good grief, I hardly would have been able to sight down the handle!  Also, if the sight is fine, then why when I mount it on the rfle backwards does it lean the opposite direction?  Is the rail flexible?  I wish I had a really good quality digital camera, with the 511 mounted, you can see the gap on the right side when it is leaning over to the left, I just don't buy that it's the receiver.   Also, why didn't my Trijicon Reflex NSN sit tilt on the receiver then?  It had a lot smaller window and I know that I would have noticed if it was tilted when I sighted through it. Like I have said before, this is the last EOTech that I will purchase and I will replace it as soon as I am able.  I just love showing this sight to other officers when they ask about it.  I hand the rifle to them and ask them what they notice about it and their response is, "Oh my!"  Then I tell them not to buy an EOTeh and buy an Aimpoint.   Yeah, it doesn't effect the way the sight works, but it is as annoying as hell to sight through it with your irons when it leans that much.  If it was just a little bit, I wouldn't mind, but this is pittiful. EDIT:  Oh, and I don't expect anyone to believe that the sight is faulty, I am sure that it is all just me.  Everyone on this board talks about the Colt "cool aid" drinkers, well, I can tell you that the EOTech "cool aid" drinkers are far worse than anyone else.  I'm sure Rolls Royce produces and product that is not up to par once in a great while, they are probably just decent enough to admit it. Are you as much as of douche that you cannot accept that you neither them or you are wrong.  Both of them are made "In Spec" however with the variance’s he is talking about (on the upper receiver) will allow for a cant... end of story...  There was a long thread about this on a Troy BUIS cant Issue and Troy said the same thing to their customers... Q :Well this effect your Point of aim point of impact ...  ? A:  NO Its simply cosmetic... Keep on thing in mind, these, along with any another part for these rifles are made for one think.. Killing... and Whacking Tangos... and protecting life’s of those you care about !! If you focus on the small stuff like this... You need to find yourself another job.. or hobby if you choose !

Uh, grow up guy.  How old are you ?


There probably isn't a member here that would be satisfied with a sight that tilted this much, whether it's just cosmetic or not.

Grow up ? Ha...  My friend, I really don’t care what you do or how old you are.. plain and simple.. You are being ignorant !  Can it be possible for one slight minute that your upper could be FooKed up !  With all of the sub contractors out there doing lots of work for all the industry Major manufacturers, don’t you think for one second that it could be your upper ?  

What kind of EDM wire gauges are you using to validate your upper as being "In Spec" ?

Be Real...  You not deal with idiots here.

Quoted: It's all mounting hardware for the 1913 rail, so it should be "apples and oranges" at all.

They mount different ways, and the contact points are different.  You are stuck in cop mode of "its right or its wrong".  I don't doubt you have an issue with your equipment, but you are missing what people are telling you.....  

Quoted: Grow up ? Ha...  My friend, I really don’t care what you do or how old you are.. plain and simple.. You are being ignorant !  Can it be possible for one slight minute that your upper could be FooKed up !  With all of the sub contractors out there doing lots of work for all the industry Major manufacturers, don’t you think for one second that it could be your upper ?   What kind of EDM wire gauges are you using to validate your upper as being "In Spec" ? Be Real...  You not deal with idiots here.

Try spell check guy, I might be able to understand a little better.

Quoted: Quoted: Grow up ? Ha...  My friend, I really don’t care what you do or how old you are.. plain and simple.. You are being ignorant !  Can it be possible for one slight minute that your upper could be FooKed up !  With all of the sub contractors out there doing lots of work for all the industry Major manufacturers, don’t you think for one second that it could be your upper ?   What kind of EDM wire gauges are you using to validate your upper as being "In Spec" ? Be Real...  You not deal with idiots here. Try spell check guy, I might be able to understand a little better.

Oh thats a good one... how mature is that.  Instead of facts now you reduce yourself to mudslinging because of your ignorance to the topic..  Good mate, you are the smart one... you corrected us, know that I know you can spell, I guess I should just sell all my guns and ETS.. no reason to stay in the fight now ...    jackass....

Just be real and think @!

btw,  I wont edit my grammer in the past post (not spelling btw) I can at least see where I am wrong...

Dear INTrooper4255,

You just don't get it.  It's your rail.  Check the spec!  If you're so adamant that you can't look at the specs and measure your rail (It's not rocket science), then take Dennis Finnegan's or Boom's offer and sell your EOThingy.

The reason your other rails and sights don't cant is the way they clamp to the rail.  The EOTech is made to fit rails that are in spec.  Even if the top of the rail is flat, the EOTech can sit canted because of the width of the rail, OR the angle of the sides of the rail.  The side angles of your rail must be each be 45 degrees.  If these are off, the EOTech can sit canted.  It's not a POS sight.  I don't think the US Special Forces, DEA, ATF, FBI and about 500 other police departments and Special Forces groups around the world would have adopted it as standard equipment if it was.

Maybe you're just an Aimpoint fan and like to flame EOTech.  I've offered to email the 1913 rail specs to you.  I doubt that you'd admit it even if you did find your rail was out of spec.
I'm done with you.

I am new to the AR world.  With that in mind I have not decided on any optics at this time, but I am reading all the feedback I can concerning such matters.  With the understanding that there are pros and cons to all products, it seems to me there would be a far greater chance of a milled rail being more out of spec than a particular sight.  With this in mind, what is the most accurately milled rail system on the market, ( I may be opening a can of worms here !!!) whether for mounting sights, lights or other accessories? Thanks for y'alls time and input.

Oh, I just have to jump in here on this one! Not for flaming but just to say that I am damn glad I bought an EOTech earlier this month after reading this thread. Dennis... your professionalism is rivaled by none.

In 1997 I had the distinct pleasure of qualifying  with a M16A2 on this beautiful little piece of dirt called Parris Island. I shot expert, of course, with the same rifle I was issued the third day of boot camp - happened to be my 19th birthday - best damn present I have ever received!To stay on topic, you could hold that weapon by the carry handle and move it side to side and watch the upper and lower slide around like you wouldnt beleive. The thing was loose as a ... we won't go there. Now why in the world did it do that? TOLERANCES! Sure, she was loose, but damn did she work great.

INTropper... you are right... you are not an engineer. So you wouldn't understand the concept of standardized tolerances to ensure the widest range of portability and after market modification. Hence the reason I can swap my Bushmaster parts with my brothers DPMS parts and they still work perfect. As Dennis spoon fed you above, tolerances are in place so that manufactures do not go out of business machining parts down to an extremely tight tolerance. That is just how it is.

On another note, by not putting your money where your mouth is and actually giving hard data, as Dennis did, you are only prooving that you are only here to whine and do not really care enough to proove your case so that EO-Tech can either make a better product or fix the one that you have. Instead of making the product better, thereby making the entire AR weapon system better, you would rather bash EO-Tech and provide no solid background for said whining. Now what does that make you? <Rhetorical Question>

Your new nickname is Officer Kelso.

Oh, Dennis... my EO-Tech sits perfect on my Samson MRFC rails. Awesome product.

http://www.avrid.com/files/T_ARPlain.jpg

ATTENTION EVERYONE.

My math was wrong, and to additionally show that I don't have an issue correcting or admitting mistakes; my interpretation of the math (and a limited explanation provided me) on the schematic was incorrect. I am not an engineer either, BTW.

The measurements are not .8" but smaller. However, there is still a variance in the possible dimensions which account for the cant issue. The measurement takes into account the use of geometric dimensioning and tolerance. It is more complex than a simple measurement but the variance still exists.

I apologize for posting incorrect numbers, but the point remains the same. Thanks for your patience.

If my EOTech sit like troopers, I would be pissed also, I dont blame him, however mine is perfect on my RRA and I love it.

I have a Rock River Entry Tactical and purchased it with the EOtech Dominator site mount, with the intention of eventially getting the EOTech sight.  Sure look forward to it lookin good.  

Manx, could you email me the .pdf file along with some basic instructions so that I can check my rail. I just got my first AR before Thanksgiving and want an Eotech sight, but want to make sure the rail is in spec before I go mounting pieces on at the supply house or gun show.

These specs?

TAG! I just received my Eotech 552 (Nov 18 date) Will get it mounted up tonight after work.

TAG

tagged.. I love my Eotech 512 and plan on getting another.

Quoted: tagged.. I love my Eotech 512 and plan on getting another.

Same here

Have two Eo's and love them, but they both sit canted on my rifles also....doesn't bother me enough to freak about it or replace, but did bother me when new.....

One on a Colt and one on a Rock River....

Mounted up my 552 on my rifle- no canting issues at all. Can't wait to go out and shoot it!

Quoted:

img212.imageshack.us/img212/8225/img08181zu.jpg
img212.imageshack.us/img212/3043/img08155wb.jpg




 Dude, you can get a new upper from Pete [RRA] for a hundred bucks and fix that shite.

I had the same problem with a 512.  I took it off and then reinstalled it, holding it down on the side that was off.  No problems now and its straight.  Who knows, operator error for me?