I have one in .177, the only ones it groups with consistent are the jsb exacts 4.52, and on doc, everyone else does too. Whether the .22 barrels are any diffrent I don't know..but I do know a lot of people are using jsb in the daystates (walther barrels) also give your barrel a clean ,because when I had mine it had lube in it to stop from rusting, the power crept up an groupings shrunk. The huntsmans are awesome. Another tip, my swp fill pressure is 220 and I always fill to 200-210 because at 220 I find the pellets are a little higher than zero , also top up just above 100bar marker on gauge 1