Originally Posted by matt_keyboardfury
That trick actually won't work on a Alpha Black. You would have to adjust the spring somehow to reduce air. The CO2 adjuster on a blowback tippmann just disrupts the airflow.
More restricts air flow. Less air flowing out the front, same'ish air going out the back (maybe a touch more due to pressure in the valve falling off slower, but that's still a pretty small hole on the back end of those valves). So a net reduction in air usage. True it's a marginal increase in efficiency compared to a proper respringing, but every little bit helps. Plus too light of spring can also overly reduce recock force, leading to less reliability.
On a target shoot you want a gun like that to recock with full force but have just enough velocity for the ball to reach and break on the target without a too noticeable arc.
Velocity consistency is almost irrelevant in this situation. And if you're handing out prizes it may even be a bad thing. We had a cowbell about 30 feet away as our primary target. If the shooter hit it 10 for 10 they'd win a free rental package (entry and gear for free, paint not included). One sharp shooter kept coming back, won enough passes for his entire 10 person birthday party.