Expect between 75-100 rounds out of one CO2 powerlet. If it's a full-auto gun, you'll get a lot of cooldown and you'll get fewer shots. For example, out of my TF11, I can get about 120 shots in semi firing slowly. With short, controlled 3-round bursts, I can get about 100 rounds. I'm lucky to get 75 if I spray in full auto.
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