The early m77 would accidental discharge. I think this applies to only pre-warning label rugers, which were pretty early. Either way JCalhoun is right, just call or contact Ruger to see if yours has been or needs to be fixed.
One of the most important pieces of equipment that you will take hunting is a good quality pair of optics and they take some care to give you the performance that you want. So here are a few tips.
Use some alcohol and cheese cloth to clean the lenses. I will usually pick up an extra cleaning kit from my optician when I have my eyes examined.
Don't touch the lens with your fingers. If there is a stick or a bug on them blow it off.
Use the lens covers. They are there...