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MonkeyHEMI
10-04-12, 14:09
I know the issues with handguards not being completely stable and potentially causing loss of zero. I'm not worried about that and am only looking for input on the actual usability of a RDS when it's pushed forward more.

How far can one actually place their eye from a RDS and still see a usable dot?

Does distortion of any sort through the lens become a problem?

I'm thinking of installing one at the end of a 12" handguard.

So anyone have experience with this? Maybe know of one brand that would allow more distance over another?

militarymoron
10-04-12, 21:24
why would you want to mount one so far forward?

lethal dose
10-04-12, 21:30
I know you don't want to hear it, but there is no way you could justify this other then having and a1/a2 upper. In that case, I'd consider a gooseneck (personally, I'd stick to irons with a fixed carry handle). To answer your question, I guess you could put it out as far as you wanted as long as YOUR eyes could see it. All this to say: in no way, do I recommend this.

MonkeyHEMI
10-04-12, 22:04
The intent is to speed up targeting. I have a 3x fixed primary and will be experimenting with a RDS in the far forward 9 o'clock position for rapid transitions between sights. The idea with placing it as far down the barrel as possible is to keep it from interfering with field view. I've used guns with 1 o' irons and while rotating a few degrees was adequate I want to see if my eyes can adapt to this style and have a more rapid/fluid transitions between sights.

Maybe someone could provide input on which sights have the widest eye opening, or rather which may be easier to view from way back. I'm looking at the RMR because of it's selection of large MOA dots and it seems like it has a fairly large viewing area.

lethal dose
10-04-12, 22:08
Viewing area does not exist in a non powered RDS. It's a figment of your imagination. Also, putting the RDS farther forward will actually slow target acquisition down.

misanthropist
10-04-12, 22:14
A number of years ago I had an M14 with a scout mount with a red dot on it. That must have been twenty inches from my eye.

At the time it seemed more reasonable than it does now. Lots of guys ran forward RDS optics back then. Also .308 was $300/1000...so yeah, that was a while ago.

Anyway one thing I'll say for that approach...by the time you're looking through the optic, the gun is sufficiently aligned with the target that finding the dot sure isn't a problem.

I never had any trouble with the dot being out that far as far as seeing it goes, but I was fairly young and had very sharp vision so I'm not sure what it would be like for most people.

Anyway I wouldn't do it today, but it can be done. I would be curious to hear the reason for wanting to do it this way, though.

MonkeyHEMI
10-05-12, 12:07
Viewing area does not exist in a non powered RDS. It's a figment of your imagination.
Maybe you misunderstood. Viewing area 100% exists. It's the area viewable from the opening for the eye (outlet). Even on the RMR the unit has a certain amount of lens area that can be measured exactly by it's width

Also, putting the RDS farther forward will actually slow target acquisition down.
That sounds like a pretty relative statement.



A number of years ago I had an M14 with a scout mount with a red dot on it. That must have been twenty inches from my eye.

At the time it seemed more reasonable than it does now. Lots of guys ran forward RDS optics back then. Also .308 was $300/1000...so yeah, that was a while ago.

Anyway one thing I'll say for that approach...by the time you're looking through the optic, the gun is sufficiently aligned with the target that finding the dot sure isn't a problem.

I never had any trouble with the dot being out that far as far as seeing it goes, but I was fairly young and had very sharp vision so I'm not sure what it would be like for most people.

Anyway I wouldn't do it today, but it can be done. I would be curious to hear the reason for wanting to do it this way, though.

I'm pretty young still and my eyes are pretty well trained :)

Glad to hear its a feasible idea. I picture it being a lot like a shotgun sight with slightly increased aiming capabilities. Something my eyes should be able to train to use by just switching from right to left.

militarymoron
10-05-12, 15:52
my .02. i wouldn't mount it in the 9 o'clock position. i'd get an offset mount that puts it just to one side of your primary (11 or 1 o'clock), so you only have to rotate the rifle 10 degrees or so. if it's in the 9 o'clock position, how are you going to sight through it?
if you're looking for more rapid/fluid transition between sights, putting the secondary further away where it requires you to rotate the gun more isn't going to do it.
are you shooting right handed or left handed? if the RDS is at 9 o'clock, and you're right handed, where's the support hand? will it get in the way of the RDS? what's going to happen to cheek weld and stock position in the shoulder when rotating the rifle that much?
those are larger questions to me than whether you can use an RDS that far away from the eye. an RDS will work that far away - it's the same as mounting them on handgun slides, and those are at arm's length.

lethal dose
10-05-12, 16:59
Explain what you mean by viewing area. You calling it the same thing as field of view?

MonkeyHEMI
10-05-12, 17:47
Mil
I appreciate the input but I'm not asking for input on the concept. What works best for me may never work for anyone else. I'm asking for specific technical info and the thread was created with the idea of gathering info that concerns me, not you or others.

Not at all trying to be a jerk.. Just making sure my thread stays on track so I can collect relevant info.

Lethal
I would define a units "field of view" as it's maximum view of the field. Field of view also implies that it's the devices view of something.
That units viewable area would be the area on the unit occupied by a viewable lens which allows viewing through the device. Opposite of "field of view" the term "viewable area" implies something to be viewed on the device.

militarymoron
10-05-12, 21:29
Mil
Not at all trying to be a jerk.. Just making sure my thread stays on track so I can collect relevant info.

how you plan to employ it is relevant info, since your original post included its intended usage. if all you wanted was technical info, this would have been enough:

"How far can one actually place their eye from a RDS and still see a usable dot?

Does distortion of any sort through the lens become a problem?"

the technical answer to those questions are:
"Further than you need. i can stand 10 feet away behind my RDS and still see a usable dot"

and "No".

MonkeyHEMI
10-05-12, 23:12
Thanks for the input. That the type of info I was looking for.

It sounds like a red dot like the RMR may be a good test piece for this.


Thanks all.

Joeywhat
10-05-12, 23:16
I love having my optics far out towards the muzzle.

Not sure why, but I shoot faster and get on target quicker.

I used to have an Aimpoint M3 about halfway down the barrel of my 14.5" middy. Besides being a bit front heavy (it was a heavy ass gun anyways) I loved that setup.

lethal dose
10-05-12, 23:57
If you are shooting both eyes open, neither field of view or "viewable area" should have any bearing on the end result. To add... if you run an RDS way out, how do you plan on utilizing said device in awkward positions such as urban prone from cover? You want, no... you NEED that optic within reasonable distance from your eye in the instance you won't be able to track the dot by viewing the length of the barrel.

ra2bach
10-06-12, 08:20
I wonder does having the optic far away from the eye change how many clicks it takes to zero...

Joeywhat
10-06-12, 08:54
If you are shooting both eyes open, neither field of view or "viewable area" should have any bearing on the end result. To add... if you run an RDS way out, how do you plan on utilizing said device in awkward positions such as urban prone from cover? You want, no... you NEED that optic within reasonable distance from your eye in the instance you won't be able to track the dot by viewing the length of the barrel.

I put a LOT of rounds downrange in non standard positions, with ZERO issues. I still liked it better then having it up close.

It didn't matter one bit to me. Just as easy to shoot SBU or urban prone.

MonkeyHEMI
10-08-12, 13:49
I put a LOT of rounds downrange in non standard positions, with ZERO issues. I still liked it better then having it up close.

It didn't matter one bit to me. Just as easy to shoot SBU or urban prone.

I'm glad to hear another has used an optic way out successfully.

Its not so much a matter of the positioning... This whole thing was about whether or not I could actually see the optic and dot enough to use that far out. If I get it and the positioning doesn't work then I'll adjust to my preference. Debating hypothetical points really does nothing which is why I've tried to avoid discussion geared towards the concept itself and tried to keep it on one specific factor (distance from optic).

I've fired is some pretty damn unconventional positions successfully and am very comfortable tackling that issue through trial and error with the optic. Heh I'll even be seeing how it does with off axis rapid sighting for ranges up to 25m (which is a large part of why I'm putting it at 9'o and don't really plan on rotating to use it). If it doesn't work it doesn't work and I'll try other ideas. Either way I plan on developing a system I can use extremely rapidly at a myriad of ranges with minimal equipment and 0 need for adjustment.

Failure2Stop
10-08-12, 14:14
Well, since you got the info you wanted and don't want to listen to any input on your concept, I'm going to go ahead and shut this down before it gets really silly.

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