Airforce barrels

Hey I have the .25 condor ss also. I would like to get a .177 barrel but would need to buy a new air bottle made for it. But recently I bought a super hat. It is an adjustable top hat with different sized inserts to restrict the air coming out. The gentleman who sold it to me said i could use the smallest insert and use that for a .177 cal. barrel. Maybe someone else has tried it?