I don't know about the orings at harbor freight. I just ordered with the breech, orings, transfer port seal and barrel from Crosman. If you change to 22 cal then you will need a 22 cal bolt too. Don't forget the oring that goes on the bolt. Crosman offers the little plastic stock for about $25 iirc.They are not that great, but I do have several kits of them for other uses.Bought my main O-rings from Magnum Air Power and Amazon by the hundreds.Hunter
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