Yup, you'll get a lot of shots out of a can, likely double what any GBB would be able to have. As you said, all the gas is sent down the barrel, none is wasted on cycling the action.
As for knowing when you buy another can, go by the liquid sound in the can, don't try to keep a record of the number of shots fired. When the can sounds low, it'll still fill, but you'll get less shots per fill mainly because you'll be getting a lot of vapour and not liquid into your mag.
|