A great quantity, unless empty, which implies great need
Similar to a barn, in that a full barrel indicates plenty and an empty one indicates want.
If you are banging a stopper into a barrel then you need to secure what you have.
A full barrel points to abundance; an empty barrel indicates bad times ahead.
If the barrel in your dream was upright, full and/or in good condition, it forecasts financial security. But if it was empty and/or rolling, it suggests you should take measures to protect your position.
An upright and full, prosperity; if rolling and empty, hard times to come.