Ian
Notorious member
or to exceed the leads ability to grip the rifling at the start of the journey.
Or near the end of the journey. This is what I see building up in the blast chamber, brakes, and on baffles when running cans with HV, uncoated cast. This is kind of like the relax point with some lubes you see when the lube doesn't thin out enough near the end of the barrel and the lube dumps out as the pressure falls off...except it's with alloy washing out instead of lube. Drive side abrasion makes gas leaks and lead dust blows out ahead of the bullet. Lots of stuff we don't see happening until there's a spot to catch what's coming out of the muzzle. I think it's fixable by tuning alloy, lube, and pressure curve, but I also think that at a certain point when pushing things up a paradox of alloy strength and lube viscosity creeps in where you just can't go any faster without some washout. Powder coat fixes that issue so easily I haven't bothered to really work out the details with regular lubed cast .22s.