Originally Posted by
Jippo
ACOG will not just drop dead. Tritium will eventually diminish but it won't be a sudden drop. I just recently sold a TA11 which was made in 1999 an was still fully operational. Tritium will half it's brightness every 12 years, meaning that it'll drop down to 1/2 brightness in 12 years, 1/4 brightness in 24 years, 1/8 brightness in 36 years, etc, etc. The scope will be mechanically busted if it is in use before the tritium goes out. Also, worth considering is the fact that the with the fibre optical modes the tritium is only used in the most darkest of conditions, because the fiber will collect light even in low light conditions.
Added to that ACOG has etched reticle, which will work even if the fiber or the tritium areout for a reason or another.