The EBT cards will never go blank, because no money actually needs to be in the account to give them a balance. Also, it would point blame and anger at the government.
However, after a cycle or two of not being paid, or being paid pennies on the dollar, retailers will cease accepting them.
Interestingly, this is almost precisely the same scenario that I have been envisioning.
Also, I know very, very few shooters/hunters that only own one rifle. This country has millions of armories.
Good point about the multiple-gun ownership of gun enthusiasts. They are like golfers buying another new driver or putter. I guess ammo will be the biggest issue, and many are stocking up.