Originally Posted by
angrybear
Well for each shot you take he volume of air remaining in the buddy bottle will be less so the pressure will fall.
How many shots cause what pressure drop depends on what power it is shooting, can you chrono it.
Filling right up to max is not a good idea, always stop 10bar or so before, the extra pressure can make the first few shots very ineffective.
Also filling causes heat in the bottle, & warm air expands, so once it had cooled & contracted for half an hour it would have dropped down from 230 anyway.