Red Dot Ops

[Werewolf]

Bought me a Red Dot 1X45 scope to mount on the rail of my AR-15. Mounts fine.

I zeroed the thing by placing the irons on the bull, locking down the rifle, verifying the irons were still on the bull then adjusting the Red Dot so the dot was on the bull.

It was - and it seems I my have been wrong - my understanding that once you get the Red Dot zeroed that where ever the dot is regardless of the angle you're looking from that's where the bullet hits. Is that correct?

If not what's the point of a RED DOT - maybe mine isn't working right. With the rifle locked down and iron sights dead on the bull when I move my head around and look thru the scope the dot moves all over the place. This makes it useless. The only time the dot is dead on the bull is when I look thru the optics dead center. With no reference to center that's pretty much impossible.

What am I missing? Is my Red Dot scope not working correctly? Frustration builds but I don't want to take it back to the dealer if it's working right and I'm not. Right now the thing is useless because either it's broke or I'm broke.

 

[Harry Tuttle]

400 dollar Aimpoint red dots are paralax free

30 dollar BSAs are not

 

[P95Carry]

Don't panic ... as Harry said it is a parallax problem. I have a fair number of cheapo red dots as well as better ones .. but you need to be aware of the problem and work around it.

IMO .. all you need to do is discipline yourself to centering the dot in the optics ... and you should find it'll perform very well. I get the impression that the parallax in these is non linear .. in other words ... from max deflection when dot appears near edge of view field .. to getting it to centre is an exponential curve.

What I mean is, describing it the other way, that on or very near center is probably all fine ... but as dot moves towards edge .. loss of accuracy gets worse quicker and quicker, until when at edge possibly no good. I've not experimented with extremes near edge .... I just make sure I am pretty much on center. It does not seem difficult to get dot on center at all.

 

[Werewolf]

Thanks for the info...
Kinda figured it was something related to parralax but wanted to be sure.

You called it on the BSA.

Still the whole point is quick acquisition and if one has to center the dot then for me at least iron's are just as quick - actually quicker.

So I guess the Red Dot goes in the drawer. Maybe a long eye relief 4X scope is in order instead? I won't be spending $400 on a Red Dot or Eotech Holo Sight - well - maybe someday - if I ever become what I consider rich.

 

[tetleyb]

Not to highjack the thread guys and if I am, my apologies. However, I just put an Aimpoint CompM2 on my AR15. I am normally used to iron sights. The red dot, when zeroed, sits just below my front sight post. Is there a way to get a different scope mount, to raise the red dot a 1/2" or 3/4"??? I can deal with the paralax issue.

 

[c_yeager]

If not what's the point of a RED DOT - maybe mine isn't working right. With the rifle locked down and iron sights dead on the bull when I move my head around and look thru the scope the dot moves all over the place. This makes it useless. The only time the dot is dead on the bull is when I look thru the optics dead center. With no reference to center that's pretty much impossible.

The dot is SUPPOSED to move within the glass. It SOUDNS like its moving a little too much (paralax) But moving a bit is what its supposed to do. The idea is that no matter what angle your looking through the glass the dot is where your bullets are going.if you move your head using the iron sights you will see the front and rear sights become misaligned. The way the red dot works is like tying a string between your front and rear sights and the 'point of aim on the target'. Its movement within the glass is actually the movement of your eye. To test this put your rifle into a vice or secure position of some kind and line the dot up on the bullseye. Move your head a little without moving the rifle. The dot SHOULD stay on the bull while it 'moves around' inside the optic. The further away the target is the less the dot shold move REALTIVE to the TARGET. Take it to the range and give it a try.

Not to highjack the thread guys and if I am, my apologies. However, I just put an Aimpoint CompM2 on my AR15. I am normally used to iron sights. The red dot, when zeroed, sits just below my front sight post. Is there a way to get a different scope mount, to raise the red dot a 1/2" or 3/4"??? I can deal with the paralax issue.

There are dozens of mounts availalbe. what are you using know? What you probably want is to get one of several 'cantilever' mounts that will move your optic up and foreward to cowitness with the sights.

 

[Werewolf]

To test this put your rifle into a vice or secure position of some kind and line the dot up on the bullseye. Move your head a little without moving the rifle. The dot SHOULD stay on the bull while it 'moves around' inside the optic.

Actually that's the way I thought it should work. I did lock the rifle down with the irons on the bull. Looking thru the red dot scope and moving my head around results in the dot moving off of the bull by quite a bit (like a few feet). The only time it's on the bull is when looking dead center thru the scope.

If a $400 dollar Red Dot works as described above in the quote then it would be a very useful tool for quick acquisition of targets and hitting them at point of aim. As it stands now my $31 BSA is pretty useless. Live and Learn as the saying goes.

 

[jobu07]

I have one of the BSA's mounted to my Mini-14. It preforms fine for the job it's used for. Really, what it comes down to I htink, is a consistant site picture. Just practice lining the red dot up the same each time, shoulder the rifle quickly and make the positioning of it relatively natural and you should do fine for quick reactive use of it.

 

[chevrofreak]

400 dollar Aimpoint red dots are paralax free

30 dollar BSAs are not

There is no such thing as a parallax free red dot.

http://www.bullseyepistol.com/ under Tools of the Trade: click Facts and Figures About Red Dot Sights

 

[Harry Tuttle]

from the bullseyepistol site:

The remaining experiments were conducted with only two different models of sights. The 30mm sized models of the UltraDot and the Tasco ProPoint 2. They were selected because they are both in the same price range, enormously popular among bullseye shooters, and certainly very different indeed.

from www.Aimpoint.com:

NO CENTERING OF THE DOT NEEDED…..
Among red dot sights, only Aimpoint sights are truly parallax-free. This means that you never have to worry about centering the dot inside the scope. Once you see the dot on your target, you’re ready to shoot. Other brands of red dot sight can cause you to miss by as much as 12 inches at a distance of only 50 yards. That can mean the difference between a clean kill and irresponsibly wounding an animal or missing it completely.

see also:
http://www.findarticles.com/cf_dls/m0BQY/5_47/72407708/p1/article.jhtml

 

[chevrofreak]

If the dot is projected from anywhere except dead center in the tube it isnt really possible to make it truly parallax free. They compensate for the angle by using curved glass at the reflection end, but they rarely get it exactly right.

There are optics, such as aimpoint that are very very close to being parallax free, but they arent there yet.

 

[Zak Smith]

tetleyb,

There are several mounts that will solve your problem: ARMS with riser, PRI extra-high mount, the KAC or GG&G offset cantilever mounts, etc.

Check over on AR15.com for details.

-z

 

[Jayman]

I can't speak for the AIMPOINT, but if there's any parallax problem in my EOTECHs, I have yet to see it/experience it.

 

[Jeff White]

tetleyb,
Just keep both eyes open and concentrate on the dot. You won't even know the front sight is there. You will drive yourself crazy trying to put the dot on top of the front sight post.

Jeff

 

[chevrofreak]

From my experience parallax gets worse the further the sight is from your eye, and/or the closer the target is to you. Past a certain distance most red dots have very little parallax.

 

[Werewolf]

Based on the responses here I did some tests on my el cheapo 1X45 Red Dot.

I bolted down my BM XM15E2S and set it up so the irons were pointed at a bull's eye (25m .22LR slow fire) at 15m. Then I adjusted the dot to be on the bull while keeping the dot as close to dead center of the glass as I could.

Here's what I discovered.

Parralax is definitely non-linear. With dot half way to either edge horizontally there was about 1" of parralax at 15m (meaning the red dot moved away from the bull by 1"). With the dot all the way to the edge parralax was about 4". Parralax was worse side to side than top to bottom with top to bottom about 1/2 of the side to side. That seemed strange but it is what I observed - that's probably a function of how the dot is projected on the glass.

At 25m the dot at the edge created about 12" of horizontal parralax.

At 50m the dot at the edge created about 36" of horizontal parralax

At 100m the dot at the edge I couldn't measure the parralax because it went just too far off the target but it was well over 6 feet.

The parralax though non-linear within the sight seems to be linear with range with the dot at the edge.

As long as you keep the dot pretty close to center - though your error increases with range - you should stay on paper and hit pretty close to your point of aim depending on how well you keep the dot centered in the glass.

The one thing I observed that surprised me was that the distance of my eye from the sight made no difference at all in the parralax and it made sense to me that it would. I checked with eye relief at approximately 3" to around 6" and moving head from side to side and putting the dot on the edge didn't change the parralax error.

What all this boils down to is that I can live with the Red Dot now that I understand it but feel it would be more appropriately mounted onto a handgun than a rifle and is definitely not a precision sight - minute of man is probably all it's good for especially at ranges farther than 50m or so. What a rifle needs is something like an ACOGS or a holosight. I'll never get an ACOGS because I'll be darned if I'm gonna spend more on a sight than the rifle costs just for a fun gun/plinker. A holo-sight is a possibility albeit an unlikely one since I'm basically a cheap guy.

Thanks for all the info guys. I hope the results of my experiment helps some of you out.

 

[caseydog]

definitely not a precision sight - minute of man is probably all it's good for especially at ranges farther than 50m or so.

I don't own a BSA , but FWIW give that red dot a chance , betcha you surprise yourself. I find red dots to be "self centering" much like a peep sight, in other words when you bring up the sight your eye and brain will work to get you to naturally center the dot without you ever realizing it. Even if your instincts don't find exact center you will have it close to center where the least parallax error exists. Ray

 

[Engineer]

Not to highjack the thread guys and if I am, my apologies. However, I just put an Aimpoint CompM2 on my AR15. I am normally used to iron sights. The red dot, when zeroed, sits just below my front sight post. Is there a way to get a different scope mount, to raise the red dot a 1/2" or 3/4"??? I can deal with the paralax issue.

Do you have a flattop AR or are you using some kind of gooseneck mount on an A2? If it's a flattop and you don't care about cowitnessing, you could just slap a riser between the upper and the Aimpoint mount. If you do care about cowitnessing, try an ARMS 22M68 with a full-height (or cantilever to put it further forward) spacer. A slightly cheaper alternative would be the Aimpoint QD mount with spacer.

 

[chevrofreak]

Werewolf, I'm surprised your results were so terrible

My 30mm BSA has the laser off to the right side, so the parallax is very different from right to left, but the same top to bottom.

I bought a cheap Target Sports 30mm and it has very little parallax at all, which is quite impressive considering they can be had for $30.98 shipped from Ebay.

You could easilly sell the BSA on Ebay and get most of your money back out of it.

 

[chevrofreak]

As far as the eye relief effecting the parallax, between 3 and 6 inches there isnt going to be much difference at all, especially on targets that are a fair distance away. Move the scope back to about 18" (pistol distance) and look at something just a few feet away and you will see some massive parallax, with ANY red dot.

 

[Bartholomew Roberts]

If the dot is projected from anywhere except dead center in the tube it isnt really possible to make it truly parallax free.

Parallax on the Aimpoint and EOtech is somewhere around an inch at 3-5yds and zero by 50yds. That may not be truly parallax free; but it is close enough that they aren't too far off in claiming it in their marketing material.

 

[P95Carry]

Werewolf ... usual info that and it does pretty much bear out my thinking ...... glad you could check it out.

As caseydog said ... (Hi Ray! .. gotta touch base sometime when all this rain quits!!) ....... it's surprising just how much and automatically one's sighting does place the dot very close to center ... just like with peeps. Not that much of a problem.

On my handgun dots (and my cannons have Millets which are quite good re parallax) .... it is occasionally a case of ''finding'' the dot, because at arm's length it can be elusive! However, even with that, once found, again ,... centering is instinctive. They sure work better for me than irons with my tired ol' eyes!