No problem on the barrels, the small white ones I have had out 4 years now w no problems and they get beat up bad...the best are the 59 gallon pickle barrels and that one has been out 5 years. I have found them all broken loose at times and over 100 yds away, usually the swivel that breaks. Now I am using 2 cinder blocks on the other end to keep them in the area, works great.
The inside washer was still on top of the barrel as you were tightening the nut down unless you had a spare.
Really like your new drone, is that the top of the line one you were talking about?