Quote Originally Posted by DesG View Post
The bore of the le Page is 9mm diameter give or take. The chamber where the powder goes is actually 7mm diameter for a depth of about 8mm. With a small bp charge it's possible to have a small gap between the powder and patched ball. Not enough to be a hazard but possibly enough to be inconsistent perhaps. This is number 8721 in my book of excuses for missing the target. I've fitted a 7mm drill bit on a rod to clean out the gunk in the chamber every ten shots or so. It's quite suprising how much builds up in there quite quickly, changing the size of the chamber, (number 8722). Maybe the filler helps. The bloke Tac mentioned who shoots rather well for Pedersoli uses an equal measure of filler to BP.

Added to the above, I've never had a patch burn through while using filler.
Thanks for the explanation DesG. I was puzzling how a filler could help, but the breech design means that it is not possible to fully seat the ball on a light charge, hence the filler.