As said, it's not the size, it's the placement.
A lot of splash off the shot goes sideways from the target. I've seen it before at another ground, this time it was a short 40mm stander. The same issue was the problem, the line went forward to a seemingly safe degree, but because target was angled along the line, the splash came back across the line.
Perhaps where this is a possibility barn doors can be placed either side to catch any splash, which seemed to solve the issue at Far Coley.
Safety is no accident.
BFTA/NSRA County Coach
CSFTA Chairman/BFTA Rep