Dave Harrell shots his with 1 gram for every 3 feet of water,so 12 feet deep uses a 4 gram float,with the ollivette or bulk shotting around 2-3 feet from the hook,with a single no1 or no4 dropper in fast flowing water to aid control and stability of the hookbait.

The bolo float is for getting right in the main flow of the river . The fish are still out there and feeding even when there’s 2 to 3 ft of extra water in the river . My experience is based on the river Severn and Wye although Avon can produce with this method . Early on I felt that the float needs to start at 5 gram and above to be most effective , given a depth of 10 to 15 ft . Smaller bolos have their place in shallower water or closer in if a bulk rig is required . I like to rest the Olivetti on a swivel then use a 2.6 inch or 3 ft hooklength with no 8 shots in pairs to represent no 6 . Usually a single bulk of no 8 results in less tangles but spread them to drag bottom sweet . Bolos are best with thick tips to show up well and to resist the boils , and to drag bottom correctly . I swapped some thin bristles for some fat peacock that is good but you can purchase the right ones now , probably from DH . Looking forward to my trial set . 😉 😉 😉

In the world champs some years ago when shy biting scardolla were the target, the Italians gradually strung shot out from an initial spread bulk to smaller and smaller shot further and further away from each other towards the hook. Easier to tangle, but it was far more effective. That’s the one I came 16th on (the Mincio) fishing the bolo for scardolla and chub. The ITs won it on the pole mind!!!