I noticed the SG-A teams use mostly P90s and 9mm pistols as their weapons (no Zats or other energy weapons, as discussed on other threads).
But what about the logistics of that decision? No matter how many clips they brought, they will eventually run out. And since they knew beforehand that they might never be able to contact earth again, there must have been a plan.
So, even if they used most of their 36 minute window to carry (tons of) crates of ammunition to Atlantis, it might take a while, but eventually they will run out of them. Then what? Will they set-up ammunition factories on Atlantis? And gather the resources to manufacture them? Doesn’t seem like an easy task!
Either that, or they will avoid firing against the wraith to save ammo.