I use a carbon fiber tripod from Hog Saddle, called the Piglite, total weight is about 5lbs without the Hog Saddle mounted.
For my longer reach hunting riles (and tgt rifles) I've mounted Swiss Arca plates to the stocks:
I have a ball head on mine, which has very, very smooth panning.
Clamping in with the Arca plate allows for the best stability.. a close 2nd that may work for your BOG is to just remove the head and use a lightweight bag:
IMHO it's just about as stable as clamping in and I've set up my rifles to balance just in front of the magazine. A huge advantage is that IF things don't go as planned and your target takes a different approach, simple lift the rifle off the bag.
I've got the Hog Saddle clamp for rifles without Arca plates, but honestly it's heavy and slow to get in and out of: