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As of yet, I am on the fence between making the T-1 or the M4 my first and primary optic (I have always used Iron sights). Would the placement fore or aft of the upper receiver also affect the addition of a magnifier? I would imagine you would want a magnifier as far aft as possible for one eye shooting.
I like the 3X Aimpoint magnifier mounted where I can use a NTCH cheekweld.
This is easy on the MRP (or any other continous rail upper) but requires some experimentation with the regular flat top receiver.
A setup that works is the stock Aimpoint M4S with the cantilever factory mount and the 3X mounted in a Samson flip. The LaRue flip sets the 3X pretty far back, and there may not be room depending on your Aimpoint and mount.
As far as the Aimpoint alone, I like it mounted about 1/2 way out over the front edge of the receiver.
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IMO I found that having red dots placed to close too the charging handle and towards the rear of the receiver gave me a lesser FOV (or so it made me feel and which grew my hate for large rear sights) I have mounted all the way up close to the FSP which I found was fast when using a VFG directly underneath the RDS which gave me faster movement and control of where I wanted my red dot (and barrel to point). Now lately I red dots mount it in between the rail space on the upper receiver and on my railed fore end. I have stopped using a VFG and started to place my hand against the lower receiver which gets my reticle lined up with the target. Try it out and see what works best for you. :D
Even with both eyes open, the dot is only visible in the area of your view that you can see through the glass of the optic. Ergo, the optics dimmensions, its placement away from you, etc. will play a role in how much of your field of view is spent looking though the tube/window.Quote:
Originally Posted by rob_s
People describing it as limiting your overall field of view is a misnomer here, as it is really only pertaining to the portion of your FOV that is looking through the optic. I find that these issues are more cheekweld related than anything, with optic size/placement to be a way to get a more lenient cheekweld.
If what you are describing is what's meant then you are correct that this is not "field of view".Quote:
Originally Posted by BushmasterFanBoy
The field of view (also field of vision) is the angular extent of the observable world that is seen at any given moment.
Another factor is the position of the cheek-weld on the stock, that affects frame of reference. If you are a nose-to-charging handle shooter or say .... a guy who runs your stock extended yet welds on the slope of your SOPMOD. I have seen guys argue about dot postion without taking eye relief distance (if that is the right term) into account.
An optic in the forward position creates some challenges during carbine class where a shooter will be in sucky positions, trying to shoot weak sided at weird angles. If the dot has a habit of walking out of objective range because it is sensitive to how the rifle is shouldered, you'll be hating life
I prefer a center/rear position on my XCR, and always have my optics mounted to the upper on AR15's, never beyond
Shoot both eyes open; you'll get plenty of visual information about the target's surroundings
Best advice I can give is lay on your side with your rifle shouldered in your off hand, arms and neck unsupported, legs curled up in near fetal position because you are trying to not break concealment from behind something small. Now how long does it take you to acquire and maintain a dot on a still target at 50 meters if the optic is far forward. If you are hunting for it, that's a problem, and you need to reconsider what you are doing.
Like an instructor once said, "I don't care what gear you run. Do whatever the hell makes you happy, but remember, bad guys don't give a shit about your problems."
When reading Erik's essay I thought that he was more referencing placement of the optic on the HG rail versus back on the receiver.
ETA- I was wrong here, see next post for clarification.
Back in the day when the Trijicon Reflex dominated the military markey for RDSs they were usually employed (or encouraged to be) near the front sight, with an absolute cowitness. The application at the time was almost strictly CQB, where slight wobble of the HG wasn't really all that detrimental to the needed degree of precision. We then figured out that most HGs were simply not structurally rigid enough to eliminate HG flex, causing POA/POI shift at even intermediate ranges. Those that only use the HG mounted optic/sights at close range are not significantly affected by HG flex, even though it may be present. The further toward the end of the HG you place the optic, the more the HG flex will affect POA/POI.
In my experience a more generous exit pupil (with magnified optics) or larger tube (with non-magnified optics) will result in faster acquistition of the dot, especially in unconventional positions. Also, the perceived size of the dot/reticle in optics such as Aimpoints and EoTechs will remain fairly constant as the optic is pushed further from the eye, which will result in the reticle/dot occupying more space within the field of view through the optic.
There is also a balance issue. Placing the weight of the optic between the hands will make the gun feel lighter than with the optic in front of the hands (see "lever") due to the mechanical advantage of the weight in relation to the fulcrum of the hand.
Different tube sizes make a difference in how much angular deviation you have available in regard to head/eye placement. The smaller the tube, the less angular deviation available. Bringing the tube rearward opens up more angle if the tube size remains constant.
With an M4/M3/EoTech alone I prefer a straight mount at the end of the upper receiver. If used in conjunction with a magnifier I prefer to use a cantilever due to eye-relief needs of the magnifier (M4/M3, no change with an Eo). If I am using a T1 I prefer to have the optic just in front of my rear sight, as it gives a more generous eye placement (rapid presentation and unconventional positions) and ghosts out the optic body better.
I hope that's the case. I have plans to go to USSA this spring and this article shook my confidence in them a little bit.Quote:
Originally Posted by Failure2Stop
I just re-read the article and my recollection was incorrect.
He is very clearly talking about moving the optic rearward toward the rear sight, actually as close as feasable. I will, however, take a few quotes from the article that I think might be pertinent and give a better perspective on what Erik is saying.
Reading that tells me that Mr. Lund is not saying that those with forward mounted optics are inexperienced, but rather inexperienced in the technique/concept of "Fighting Through the Ring".Quote:
Among the many things I look for when making my initial evaluation of my prospective students is what type of sighting system is on the student’s rifles. If the student chooses to use some type of optic, and most do, what are they using? Did they choose some type of magnified optic or did they go the electronic route? If they choose to use an electronic sight (i.e. - Aimpoint, EOTech, Trijicon, etc,) I tend to observe how, and more importantly where they mount the sight. So why is this important to me as an Instructor? Because it tells me whether or not the student has any experience Fighting Through the Ring.
He then goes on to give an explaination and example, ending with this:
What that says to me is that Erik wants to help you be better (publishing this for free access and use), and explains a technique that makes it easier to engage real threats within an envelope. He even finishes with pointing out that it's worth a try, not that if you don't do it his way you are a n00b and will get shot in the face.Quote:
What if, by simply repositioning your optic, you reduce your threat engagement times by 50%? Is that worth the time it takes to move the optic? What if it’s only 40% or 30% or even 20%, is it still worth the slight effort? Only you can make that judgment, but the answer seems pretty clear. Any reduction in threat engagement times that is gained without hours and hours of practice, by a simple repositioning of the optic is at least worth a try. Next time you go to the range, try Fighting Through the Ring and not around it.
At leaast that's how I read it.