Hey guys, I have a question about zeroing and the effect on a BDC. The range I have access to has its target areas staggered in yards (50/100/200) but the BDC reticle for the optic is designed around meters. Will zeroing at 100 yards when the BDC is designed to be zeroed at 100 meters cause the BDC to be off by a large margin? It's a difference of about 9 yards at 100 meters, but almost 30 at 300. Also, if I'm shooting M193 out of a 16" barrel instead of the M855 out of a 14.5" barrel that the BDC is calibrated for will that make a big difference as well? I would like to be zeroed so that the BDC will be as accurate as possible, but that might be difficult to do without shooting the same ammo the BDC was designed for. Thanks!