Ok, guys. I am new to this competition thing, so I am hoping someone can help out or at least point me in the right direction. I have registered for Larue's 3-gun and when reading through the rules posted on Mark Fingar's website, I am still confused. The rules says "factory configuration", so if I am planning on shooting Heavy-Tac, can I use my optic up top and a 45 offset for my BUIS? I appreciate any clarification you can offer.