I don't know what kind of a tank you like if the reticle melts that's not a very good tank.
Solid. Robust. Sturdy. You could use one to pound in a tent spike into the ground (not entirely sure why they would do that... but they did) and it would still function flawlessly.
Yes, the reticle did melt if the solid steel tube was left in the direct sun light, but Marines being Marines (masters of make-do and do-more with-less) they would find ways around that from happening.
I carried an M40A1 all over coastal North Carolina for a month through all sorts of weather: mid-50*F to low 100*F, high humidity, even the tail end of a hurricane, day and night, crawling through swamps, laying in open fields, and all sorts of other happiness the instructors could think up.....throughout it all, the Unertl never failed me once. None of the other students had any problems of reticles melting because the instructors had experienced it YEARS before and taught the students how to avoid it.
In my opinion it was a great scope, even better than most on the market today. I maintained it as instructed and it never failed me. However, it was dated technology and the eye relief was not the greatest for me.
If anyone here ever personally experienced the reticle melting in their scope PM me, I would be interested in hearing any others personal experience with the Unertl. Thanks
Mac