I just hi-tek coated a bunch of these flat nosed cast bullets. (my mold is the c109-150-fn which looks like it might be the same as yours). Im new to reloading and trying to figure out what length to load them to since they are flat nosed they will obviously be shorter than most. I loaded one .300blk to the length it would fit in my go / no go gauge. Then I loaded one really long, stuck it in the mag and let the AR chamber it then took a length off that which was a good bit longer but I assume right against the lands and grooves. Do you have any suggestions on resources to figure it out or any suggestions?