Keeping the weight of the bottle back without it getting in the way of your sight picture is the way to go, but-Single Shot? Who asked for that? I hope that's a typo or this thing is dead in the water.
I haven't seen this one before. It's pretty much what I've always wanted to do to a Condor. Anyone have one yet?https://www.krale.shop/en/artemis-p18/
I think the gun is smaller than it looks, that's only a 300cc bottle. It doesn't look like any of the guys on the youtube reviews are having trouble.