Seems like most pictures on the internet have it as far forward on the receiver rail as possible. I’m hesitant to have it on the handguard rail at all just for stability reasons.
It seems like it’s faster to get a sight picture with it mounted further back… I have no real intention of installing a magnifier any time soon. Is there any particular reason to mount it further forward?
So where should it go? This is a compm4 with a stock aimpoint mount. Also running magpul BUIS.
Mount it as far forward as you can on the receiver. If you are using a red dot sight correctly there is no sight picture because you are not deliberately looking through the optic, it is not a scope. You should have both eyes open, both focused on the target and you are superimposing and seeing the fuzzy dot on the target. An easy way to test and to practice this is to find a target or focal point about 15-25 meters away. Find your impact point or where you want to bullet to go, say the head for example, now bring the rifle up until you see the dot on the head. Repeat this several times, then tape over the objective lens of your Aimpoint and repeat the drill. You’ll find that nothing has changed in acquiring the dot. Nothing at all. You don’t need to see through a red dot optic at all to use it to make your hits.
I’m not trying to be a dick, but how in the world can someone on the internet tell YOU, where the best place for YOU to have your RDS mounted is? All that we can do is tell you what works best for us. I find weapon setups to be a highly personal thing, what is “best” for me, very well might suck for you.
As far as your question, you will normally see people mount their T1’s on the last slot (+/- a slot or two) of the upper receiver. I do mount my T1’s out further than I do my Eotech.
Hit the range with a timer and run some drills on the clock, see what location allows you to pick up your sight and target the fastest and roll from there. Set your gun up for you, don’t set it up based on what others you see are doing. Who knows, we could all be a bunch of Bubba dirt shooters. 
Another take on where to put the RDS. Fighting Through The Ring
Thank you for posting the article Kodiak. Good read. I will have to try that next time I am at the range.
If I’m reading this correctly it is stating to put the red dot to the rear as far as possible to have a greater field of view?
Yep
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This makes sense to me. I basically started this thread because I was curious a to why so many rifle I saw online had the optic mounted forward, while my small amount of testing seemed to imply greater speed with it mounted back further.you also gain a wider margin of error as far a shouldering the gun and being able to see a dot. Typos courtesy of Swype
this is a little contentious because most people will say that there is no “field of view” with a RDS done properly - that is, with both eyes open. however, I know Erik and spoke to him at length about this. maybe in this context, “field of view” is not exactly accurate as that term relates to magnified optics that present a different sight picture outside the optic.
his premise is that by placing the RDS closer to the eye on the rail gives a larger down range image inside the body of optic and that multiple targets viewed within the circumference of the RDS make it more instinctive/natural/quicker to transition the dot from one to the other, than targets which lie outside of the “ring”.
again, many will say that there is no advantage because a RDS is not magnified and using a RDS properly (with both eyes open and focusing on the target) allows the red dot to superimpose the POA and the body of the optic blurs out (like a rear iron sight). they contend that the farther away from the eye, the more this becomes the case, and the closer the optic to the eye, the more the body of the optic intrudes on their binocular vision.
I’ve trained with Erik several times using different guns set up both ways to see if there is an actual benefit to either method. I have found that what he says does have merit, though with my corrected vision, I found I get a sharper dot with the optic further out.
I think it’s interesting that Larry Vickers uses a T-1 mounted about midway forward on the receiver though I don’t know his personal reasons…
Opposite eye dominance also comes into play.
The closer to the rear the more trouble I have seeing with both eyes open so my speed would be greatly reduced.
This all also assumes the user is not planning on having a 3x magnifier or NVD mounted behind the red dot.
Also might want to try mount your RDS as far back as possible (with BUIS of course) then see how much of your strong-side periphreal vision is blocked with both eyes open. This blind spot is mitigated because between targets you’re supposed to look over your sights to get a clear field of view, but while you’re aiming, you won’t see everything. This is also mitigated somewhat because of tunnel vision in high stress environments…
This is one of the reasons I used for the final placement of my Aimpoint Pro. I originately mounted it about halfway (my sight preference) and made sure I could cowitness with my Troy sights which I fold down when not in use. Once I owned the magnifier I moved the Aimpoint forward enought to install the mount for the magnifier. I didn’t notice any difference sighting in with the Aimpoint further forward. Still sight in with both eyes open. Works like a champ.
I thought I’d end up with my Aimpoint Micro mounted more-or-less above the front of the receiver once I had everything all finalized on my DDM4v3, but I can run it noticeably faster when I have it placed just in front of the rear irons. My eyes are over the hill and picking up speed, so YMMV.
toc
I’ve basically settled on one visible slot on the receiver in front of the mount. So it’s basically a finger’s width ahead of my backup sight. Seems to keep it well out of the way of the bolt catch and charging handle (i have the big knob on my mount…) but still pretty far back…
Honestly messing around with i didn’t notice a ton of difference anywhere i could put it on the receiver rail. i really only have about an inch or so to play with before it runs off the front of the rail or hits my backup sight.
Moving an optic farther forward opens up your field of view. The farther away an object, the smaller it appears. Simple enough.
It opens the fov around the outside of the rds BUT restricts it inside the rds where the little dot you want to put on the target it. “Simple enough”.
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Yep. And you don’t need the area around the RDS for it to be effective. It isn’t by chance that the newest Aimpoints have a smaller diameter.
Thats the debate, closer or further away. No simple answer really. Personal preference and how ones eyes perceive will play a part too.
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Gotcha. Opposite eye dominance can be remedied. If you are right handed and your left eye has even slightly better vision than your right it will tend to be dominant. Corrective lenses is the first place to start and an easy fix. There are other fixes if that isn’t the issue.
In any event, sticking your face up to the tube on a RDS should be avoided if at all possible. It is a great way to tunnel in and cut out a larger portion of your field of view than necessary.
Are you severely opposite eye dominant?
I am and I find it very difficult to deal with regarding any long gun and very difficult to fix.