Trying to answer that in simple terms might not be easy. For precision shooters the rifle scope and the choice of reticle matter the most. There have been various researches on the question that which rifle scope offers the best performance. More than often we have seen Schmidt and Bender scopes being the final choice of seasoned shooters and hunters. However, there are other rifle scopes in the market today that have closed in on Schmidt and Bender. For instance, the Vortex rifle scopes and Bushnell are evolving as alternative choices for the precision shooters. In addition to these brands, there is Steiner and Kahles, Nightforce, Leupold and March have also made it to the list of popular scopes for tactical shooters.
The question is what is there in these rifle scopes that make them favourable over other several brands. The lens, of course, is a major reason. The accuracy and clear image depends on it. In addition to this there is the reticle factor. Reticles play a major role in deciding the performance of the rifle scopes. According to various scope users reticle and scope manufacturer can easily guide you to the required details about the scope model. MSR reticles seem to be the most widely used reticle last year. But it had to share its top spot with the H2CMR reticle. On the other hand the G2DMR reticle used in Bushnell scopes has also gained popularity.
The choices of reticles do not alter much every year but what changes is the list of newcomers. Almost every year a new reticle makes it to the list of top reticles due to their performance. In recent times there has been a rise of popularity for the “Christmas tree” style reticles. These allow the users for quick hold-offs in place of calling for elevation adjustment. The gridded reticle enables the users to hold the elevation and wind. Initially it was Horus Vision but nowadays these reticles are used by various manufacturers.
There are shooters who purchase a scope for a particular rifle and change it only when they need to upgrade it. With fast advances in the rifle scope technology changes have taken place in the manufacturing of rings, mounts and bases to attach the rifle scope to the firearm. Quick detachable mounts allow some rifle scopes to be mounted on more than one rifle. This factor is more dependent on the mounting system, but can be an important point to consider if the shooter is the type that wants to quickly and conveniently move a rifle scope from one rifle to another.
Finally, while choosing a rifle scope, the best shooters rely on their personal preferences. Whether you will be using a Mil-dot technology or go for a Schmidt and Bender scope is largely a personal decision. If the rifle you are choosing is a good performer, reliable, impervious to weather, consistent with zeroing, tritium filled and parallax free, the scope is good enough to opt for.