I'm just about convinced myself to purchase a TA31F for my M4 and I wanted to know if the sight would still be useful if the tritium was no longer able to illuminated the chevron. I know about the 12 years and the half-life issues so technically the tritium only glows dimmer but I wanted to know if this sight would still be useful in the daytime like the TA01NSN.

Would the chevron be black like the BDC lines on the scope or would the chevron slowly fade away making the scope unusable in daytime and nighttime.

Thanks for looking and all replies,
Leadfoot

leadfoot,
The fiber optic will still illuminate the sight during the day.  and it will look like this.
[img]http://photos.ar15.com/ImageGallery/Attachments/DownloadAttach.asp?iImageUnq=20166[/img]

At night (without tritium), or when the fiber optic tube wont pick up enough light, it will look like this.
[img]http://photos.ar15.com/ImageGallery/Attachments/DownloadAttach.asp?iImageUnq=20165[/img]

Keep in mind the tritium is only for dusk, nightime and dawn applications where the fiberoptics cant get any light and you need something other than black.

Also if in years to come we are not able to get tritium replaced, then it wouldnt be hard to rig up a glowstick or light near/on the fiber optic tube to create a backup light source.

Picture of fiberoptic tube
[img]http://photos.ar15.com/ImageGallery/Attachments/DownloadAttach.asp?iImageUnq=20168[/img]

FRO, thanks! That was exactly the information I was looking for. Too bad your not a dealer because you just convinced me to buy a TA31.

Your pictures are great but is the TA31F chevron really that bright and easy to pick up.

If so I'll probably make the TA31F the primary scope and the Aimpoint my secondary.

leadfoot
Thats part of the usefullness of the fiberoptic. It will change brightness with the environment your in without any switches.

If its an overcast, rainy day then the cheveron will be dimmer. And you'll want it to be. Just like you may turn down the intensity of the aimpoint.
If its a bright sunny day it will pick up more light and the cheveron will be brighter.

If you're sighting from, lets say a thick stand of pine trees, to a bright sunny field. The chevron will be black.

You always have something to aim with.

I wish I were a trijicon dealer also. They pretty much sell themselves.  I'm just a shooter who thinks that this is "a better mousetrap"
[disclaimer]However if trijicon wanted to have joleene contact me and send me a hat that would be nice HINT HINT[/disclaimer]



(never hurts to beg right?)

Do the doughnut reticles go black if the tritrium is gone too?

Yes.

I'v finally got some kydex and now I'm hunting a vacuum sealer type machine.  I'm going to make a snap on device that will allow the use of a photon light to supplement the tritium on the ACOG.

A couple of the guys volunteered to help beta test this.  If I use the photon III I can vary the brightness of the LED.  

Yopu know what I always thought would be a useful addition?  

a momentary pressure switch on the pistol grip, just like on a laser or flashlight, to control lit reticle scopes.  

That way, they could be left "on" and not use any battery power until you squeezed the grip.  A lot faster than turning knobs, and wouldn't wear out like Tritium.

What if your hand is injured?  Are you going to run exposed wire on the outside of the rifle?  

If thats what you REALLY want there is an OKO variant that has a tape switch you can mount on the pistol grip.  For me the quick flip of the Aimpoint takes about .5 seconds and it wont shut off.  The ACOG tritium will last so long by the time it burns out there will be a new super optic to buy.

Nah, I'm going to make the snap on mount so the photon III switch is on top.  And I'll have a hole you can access the photon through to press the constant on portion.  That coupled with the fact that you can get well over 40hrs IIRC on low power setting.  And you can cannibalize the light for regular use, or whatever.