That's all they really need. You could give the barrels and hops a clean, and check that the rubbers haven't deteriorated.
A quick squirt of silicone oil up the nozzle of AEGs, or into the cut out, can help to re-seal the o-rings. Just blow any excess out the nozzle before re-assembling.
Thanks, I am a bit wary of dissasembling them due to my absolute lack of knowledge and last time I tried to clean out the cm16 I ended up having to take it on a 5 hour drive to Zero One to get it fixed ?
A quick squirt of silicone oil up the nozzle of AEGs, or into the cut out, can help to re-seal the o-rings. Just blow any excess out the nozzle before re-assembling.