BGK, I have the same barrels. the inside of those caps are threaded for hose hook ups or valves if you look close the centerof the plastic plugs are very thin and some times at the dairy up here they pop tiny holse in them to vent the barrel so the liquid flows out easier. a 3/4 PVC pipe lug fits in there great. I am not sure why they make the barrel threads coarse on one side and fine on the other but mine are the same way. I need 6 of the plugs myself lol (3 fine 3 coarse). Curently there is 15 under my dock but im going to put 27 under it for more stabilty. it works out to be 3 rows of 9. might be overkill but I want it to be as stable as possible and 27 barrels is the most that will fit under there.

Last edited by roadjoker22; 02/21/11 03:47 PM.
A weeks worth of vacation, 59 hours in a John Deere 160, 2 logs of Skoal, 1500$ in fuel, Lots of help from the neigbors and my old man, and a wife with an open mind to let me dig a pond at are cabin. All i can say is life is good!