Rail I will be using is the Geissele 13.5 MK4 DDC. I'm not sure it's weight but I'm not too concerned with the weight of the build either honestly. The plan was a pinned and welded as short as possible rifle build. Probably will go with ADCO to pin and weld or cut if needed.

So where I'm stumped is if I should go 13.7 barrel with a KAC spacer or go with a 14.5 barrel and no spacer. The muzzle device will be a Surefire Warcomp.