What Do Night Sights Look Like After They Fade?

What kind?

Hey there:
I put the Kimber night sights on my Ultra Carry about 8 years ago. They may not be as bright as they were when new but still very visable in low light. Darker it gets the brighter they are.

I have the Tritium sights , they claim they are good for atleast 10 years. Not sure of other types.

Not that bad.

Hey again :
A cop friend of mine has a set that has been on his colt carry gun for about 13 or 14 years. They still work good. Again ; not as bright as new but still can see them in low light .

When the tritium is no longer active the night sights just stop glowing.

They look like standard iron sights.

Unfortunately, I own 4 firearms equipped with PT Nitesites (P7M8, P7M13, ParaOrd P13, Beretta 1201fp), these things had pretty-much faded during their first year of use, I know what faded sights look like.

Mine are 16 years old. Trijicon. Still glow in dim light, not terribly bright, but good enough to pick up and be useful.

The half life of tritium is approx. 12 yrs. In very relative terms that means that the gas vials should appear to be about 25% less bright after 5-6 years and 50 % less at 10-12.

In practical terms it usually makes more visible difference than the numbers would suggest, given the very small output of those tiny vials in the first place.

My rule of thumb is to replace them when I start losing good definition in dim light. So far I've only had to do this on a LEA trade-in 4586 that I bought at a very good price for a nightstand gun and my little Star M43. Both were at least 10 yrs old., the Star's Meprolites and the S&W's Trijicons, IIRC.

Trijicon lists their green and yellow lights as the longest life (warranted for 12 years), their orange at the shortest (5 years).

Trijicon lists their green and yellow lights as the longest life (warranted for 12 years), their orange at the shortest (5 years).

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The human eye is most sensitive in the green portion of the spectrum.
The efficiency of the phosphors in creating light from the radioactive decay (beta particles, AKA electrons)also comes into play.

All the tritium sights I have seen have a white ring around the tritium that acts as a kind of shock absorber. That ring also serves to help sighting in bright daylight when the glow is not as noticeable. So after the tritium breaks down beyond usefulness you will pretty much have 3 white circle sights instead of 3 white dot sights.

You can not see them in the dark after they have stopped glowing.

- Captain Obvious

They look like 3 dot sights. I've own an old 226 Sig with the factory tritium sights, if you are in a very dark room they still glow very dimly, in a room with low lighting they look like a 3 dot system.

You can not see them in the dark after they have stopped glowing.

- Captain Obvious

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Hahahaha!

Do they pretty much look just like and function just like the regular 3 dot white sights?

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It depends on the manufacturer and whether or not there are white rings around the dots. Some (e.g., Novak) do not, and will just appear as black sights in lower light.

I have a Sig 220 dated 1995 with faded night sights. You can still see them, but only about half brightness of new.

Have a model 66 with three faded green dots

Previous owner had them done 20+ years ago. Today they are dull green dots in bright light, and invisible in the dark.

I've replaced a number of sets of older night sights now, and the difference is instantly noticeable between them.

The biggest difference is between older Trijicons and new Meprolights, especially in the dark, but even outside on a bright day. The Trjicons all had smaller vials with no white ring around them. The Mepro's all have the ring and the vials are bigger. Not sure if Trijicon has updated theirs now or not, I just keep buying the Mepro's.

For some reason, people will buy your old night sights for about half of what a new set costs. I wouldnt have thought they'd have been worth anything, but I was getting about $35-40 a set for the old ones I removed, which paid for my sight tool. So I'm not bitching.

And no one has posted the most obvious answer yet? Whatever they look like during the day is what they'll look like when they fade completely.

I plan to be there

As noted above, the half life of tritium is approx. 12 yrs. This means the radioactive isotope decays to half its amount in that time period. I also recall it is like 10 half life cycles to consider the isotope essentialy 'fully decayed' (note: cutting a mass in half, over and over, will really never completely eliminate all of the atoms, but it gets close enough after 10 cycles to fool limited human eye sight.)

10 half life cycles amounts to 120 years I figure I'll be long gone before the night sight no longer emits some visible light. Whether it is useful, or not, remains to be seen .... I plan to be there

Dawn sights I guess

CWL SAID:

They look like standard iron sights.

Unfortunately, I own 4 firearms equipped with PT Nitesites (P7M8, P7M13, ParaOrd P13, Beretta 1201fp), these things had pretty-much faded during their first year of use, I know what faded sights look like.

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Contact PT.....I had the same thing on a set of night sights for my Kimber. I made the mistake of getting red/green....the red REALLY was dim, the green was far dimmer then it should have been. Got worse over the next 3 years. Finally I gave in and was going to have them replaced....but I called PT first. They had me ship them the slide and put new sights in, no questions asked. Went with green/green this time, much better. Just dont be in a hurry.....took them almost 30 days to do it.

Funny thing is, its not the Tritium in the night-sights that breaks down over time, its the pigment that glows the red/blue/green color that is broken down mainly due to 10 years of non-stop beta-bombardment from said tritium.