I have also used both the 3-12X Burris LER and riflescopes and i can probably safely say that i'll never buy another Birris 3-12X again. Here's the reason why. As a spot and stalk hunter oftentimes i have needed to take shots from prone with a bipod. At 12X the eye relief is too long for my arms. I have to struggle to get the optic far enuf away from me to shoot my rigs, even with the extension bases that r sold by Farrell and Near. I know others with longer arms than myself have also had this problem as well. With a rear grip handgun this may not be a problem, but most of my HG's are center grip. This being said the longest shot i ever made was a coyote at 906 yds. i was shooting the 3-12X Burris Ball. Plex reticle and turret comeups calcd to 1000. I was shooting from a system similar to JLK's. Here's a link to it--
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