I finally made it to the range today and shot my 20" Bushmaster upper. I shot from a bipod and no rear rest. My better rest and chronograph were not available.. Didn't matter as I wanted to see what it felt like. All shots targets are 100 yards, 5 shot groups. pretty stiff cross wind. Loads described will go from 12 o'clock then clockwise ( that to the right for you digital people The red bull is 2 Inch Diameter. ( crimped per Hoots recommendations).
250 gr FTX 37.0 gr lilgun
250 gr FTX 37.5 gr lilgun
250 gr FTX 38.0 gr lilgun
250 gr FTX 38.5 gr lilgun
300 gr XTP 28.0 gr lilgun ( high left flyer was my fault)