I'm not going to pretend to be a sniper. Figure 500 rounds to break in the rifle, clean it and leave another 500 rounds waiting in a can.
Don't need mountains of ammo. They're will be plenty when the SHTF.
Ammo will be currency. There may be a lot around, but I’m not convinced that would be the case. But you will have to barter for it. No matter how much of it there is out there it won’t be easy to get cheaply. We should all have learned that lesson from the Obama shortages. When you bring survival into the mix, it will really change the equation.