In article ,
Larry Jaques wrote:

If they're dual-capped barrels, perhaps you could pressurize the small
hole with air and pipe the large outlet for a quick and dirty emptying
for a lot less cost than pumps.

Good, but be sure to use a regulator and keep the pressure reasonable so
you don't ruin the drums. Might even work with an open end barrel if you
have a good sealing clamp-on top.

--
Cats, coffee, chocolate...vices to live by