Hello all, I've been a member of ARRSE for some time, but didn't realise there was a shooting forum. Biff. I've got a Martini Henry in 577-450 and I use it with pyrodex loads with an oatmeal filler. I've been advised that this is unsuitable (even though I've had no probs with it for about 4 years) and that using oatmeal is liable to cause a ring bulge in the chamber. What do other forum users use for their filler. I'm reluctant to use cotton wool because of possible fire risks on grass ranges during the summer.