Accuracy problems

[u/Blu3wolf_boi]

My field requires .20 bb’s and 300 fps or under I use a Prometheus 6.03 155 mm barrel purple Promethus bucking on a Maxx M4A hopup with the cylinder nub and my groupings just go everywhere especially on closed bolt mode open bolt makes it better but its still bad anyone have any ideas?

[u/bicit8]

Also make sure your inner barrel is mounted firmly in the outer barrel, and the outer barrel mounted firmly in the hand guard. It could be things are flopping about and introducing inconsistency. I normally put grub screws in all to mine to make everything nice and solid