[Ando]

I say you fix the leak out the back first then deal with the lvl 10. Since it's a new piston. I would ck your piston oring and completely clean out the cavity it sits in. Any kind of dirt or bad oring will cause a leak like that.

There's been one case that I know of that a new piston from AGD was also bad but chances are....No.

As for your barrel leak. Fire and hold the trigger down. If it's still leaking out the front, It's your on/off assy causing the leak. Again, remove, inspect, replace if needed and clean EVERYTHING out, then oil and reinstall.

If it stopped leaking with the trigger held, you might have just wore in the carrier oring. Go down a carrier size but remember to use the exact same carrier oring (the center white one) when swapping out carriers. That should fix both problems.