I'm more on the lower end of the spectrum.
I play an average of 3 times a month. I have a KSC Glock 19 GBB, with two magazines, and a KJW Beretta 92F GBB with 4 magazines. I typically load 15 BBs in each magazine. I also share my gas on a frequent basis (pun intended), and I use my pistols a great deal.
A coleman tank can last me 4-8 months.
Even when I had my WA M4 GBB, I don't think I even went through that much more (I always brought 6 magazines to the game). The M4 was clearly eating up more gas, but I always seem to have more left in the tank than I think I should have (until eventually it goes ka-put).
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Nabisco Lobstrosity
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