Sbr + acog ftw

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doc540

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had no idea it was this good

TA31RCOM4 4x32 USMC

(but doesn't work well as with prescription lenses)

I called Trijicon and asked about its lack of a focus adjustment and the tech gave me a straight answer:
"It was designed for young soldiers with good eyesight and those needing glasses were adjusted to use this optic."

See? Old Fekkers understand that kind of tech talk.:eek:

d2085ea4-fc02-45b7-ac5b-41b2e3b65758_zpsf272727d.jpg
 
Both reflex red dot and hollo sights project the dot to infinity which is a huge plus for us old folks with presbyopia (inability to focus at more than one focal plane).

If the dot is blurry that is a good old-fashioned astigmatism which has little to do with age. You just need newer/better glasses. Find a doc who will let you bring your rifle or just the sight in with you when getting your refractometry done.

Mike
 
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Yes, you are correct.

But this is a perimeter/home defense rifle so I won't be wearing dedicated lenses if the hurricane zombies come over the fence. ;)
 
Arizona_Mike said:
Both reflex and red dot sights project the dot to infinity which is a huge plus for us old folks with presbyopia (inability to focus at more than one focal plane).

If the dot is blurry that is a good old-fashioned astigmatism which has little to do with age. You just need newer/better glasses. Find a doc who will let you bring your rifle or just the sight in with you when getting your refractometry done.

Mike
Click to expand...

I'm not so sure, at least with my eyes.

With my cheap red dots or my EOTech, the dots/reticles are in perfect focus with my middle lens of my trifocals. While using my far vision upper lens, the dots are a tad blurry. But of course the target is clear with that upper lens.

Same goes for my older progressive lenses, I tilt my head into that middle zone and the dot gets sharper.

In my opinion, the "infinity" focus (that has been told to us for years) on a red dot is more like 5 to 10 feet.
 
The Trijicon tech confirmed today the ACOG wasn't designed for shooters with corrective lenses and having to wear prescription glasses could be a problem.

At least he was straight up about it. :)
 
Is that a Yankee Hill Machine front sight base? How do you like it, is it secure enough? That looks like quite the handy package.
 
Haven't tried this myself, as I don't have an ACOG, but if you wrap a bit of black electrical tape around a portion of the exposed fiber optic, the reticle really sharpens up. (Attached a crappy MS Paint pic for clarification, but it serves it's purpose).

Worth a shot. Let us know what you think if you try it.
 

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chicharrones said:
I'm not so sure, at least with my eyes.

With my cheap red dots or my EOTech, the dots/reticles are in perfect focus with my middle lens of my trifocals. While using my far vision upper lens, the dots are a tad blurry. But of course the target is clear with that upper lens.

Same goes for my older progressive lenses, I tilt my head into that middle zone and the dot gets sharper.

In my opinion, the "infinity" focus (that has been told to us for years) on a red dot is more like 5 to 10 feet.
Click to expand...
It's optical infinity. In the case of reflex sights the dot is at the common focal point between two lenses which projects to infinity. Holo sights work a little differently but the result is the same. 5-10 feet would give horrible parallex.
 
Arizona_Mike said:
It's optical infinity. In the case of reflex sights the dot is at the common focal point between two lenses which projects to infinity. Holo sights work a little differently but the result is the same. 5-10 feet would give horrible parallex.
Click to expand...

The definition of optical infinity doesn't work out with my reflex sights or holo sight. If it were true optical infinity, wouldn't the lens on my glasses that can focus on a target at 50, 100, or 200 yards make the red dot look focused?

EDIT: It looks like optical infinity of the human eye is about 20 feet.

My particular two sets of trifocal/progressive glasses don't focus the red dot or holo sight at that 20 feet. After re-checking, the red dots and holo-sight is still focused on my middle glasses lens which is about 5 to 10 feet.

Not a big deal as I'm just used to somewhat blurred red dots. It is still much better than really blurry front sight posts. :)
 
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chicharrones said:
The definition of optical infinity doesn't work out with my reflex sights or holo sight. If it were true optical infinity, wouldn't the lens on my glasses that can focus on a target at 50, 100, or 200 yards make the red dot look focused?
Click to expand...
No.
EDIT: It looks like optical infinity of the human eye is about 20 feet.
Click to expand...
Read some of the articles that link brings up. 20ft is 0.16 diopters from optical infinity. Not a huge difference in terms of focus but important for parallax.

My particular two sets of trifocal/progressive glasses don't focus the red dot or holo sight at that 20 feet. After re-checking, the red dots and holo-sight is still focused on my middle glasses lens which is about 5 to 10 feet.

Not a big deal as I'm just used to somewhat blurred red dots. It is still much better than really blurry front sight posts. :)
Click to expand...
You are confusing myopia/hyperopia (focal point in eye being in front or behind the retina) which is what changes in vertically in bifocals/trifocals/progressive lenses across the lens (the spherical part of the correction--the first number on the prescription) with astigmatism in which the focal point is not symmetic regardless of the main focal length of the eye. This is the trapezoidal part of the prescription (next 2 numbers). I suspect that the astigmatic correction of your lens is optimum at that point even if the focal length is slightly off.

Even the typical 70 year old has one diopter of adjustment range left in his eyes.
240px-Specrx-accom.png

Mike
 
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Okay. I'm really not trying to take this thread away from the OP's rifle, but I was trying to relate to his vision through his optic.

So, I think that since the OPs reticle in his ACOG is blurry to him, I probably would have the same situation looking though an ACOG.
 
I called Trijicon and asked about its lack of a focus adjustment and the tech gave me a straight answer:
"It was designed for young soldiers with good eyesight and those needing glasses were adjusted to use this optic."
Click to expand...

Funny, I can't use irons worth beans, but the apparent viewing distance of my TA31 reticle is far enough out that I can can still see it clearly. The Russian PSOP are even better for me -- usable before Lasik corrected my hyperopia when I was near the limit of diopter correction on most scopes.


But Mike is correct about optical infinity and accommodation. Years after Lasik I still "see" 20/20 about 6+ feet out.
 
Okay. I'm really not trying to take this thread away from the OP's rifle, but I was trying to relate to his vision through his optic.

So, I think that since the OPs reticle in his ACOG is blurry to him, I probably would have the same situation looking though an ACOG.
Click to expand...

Ummm, I shoot with corrective lenses and I have no problems with ACOGs ranging from the 1.5x through 4x models. I simply never tried mid-range shooting with any of the higher magnification versions.

The severity...err..strength of your prescription just might be a very important factor.
 
True but with the progressives the strength increases as your eyes move down the lens. The sweet spot on mine are about half way down.
 
You're not understanding or I'm not explaining it clearly.

When sighting down a rifle's sight plane to the front sight, to see it clearly through the mid-range area of my lenses, I'd have to lift my head off the cheek rest.

There's no way to access that area and keep a firm cheek plant.

Hope that helps.
 
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