I'm interested in what JB has to say, too, but I'm guessing that part of his motivation comes from the fact that the GB scopes come with Leup target turrets that have custom BDC engraving on them. Just a guess, though. He obviously chose those turrets for a reason when he was spec'ing out GB scopes with Leupold...
I think you can get a custom BDC for the M1's if I'm not mistaken, I'm guessing that JB like's the fact that the TT can be covered!
