Let me add my .02 to this BS. With 50,000 psi behind it, nothing is going to stick around very long in a gas system on a high powered rifle.
I have heard this particular line of BS for the last 30 years, but so far have not been able to actually see it take place,, and I have looked.
I concluded it was a crock around 1990 when I first heard about it.
A Water-Jet Cutting machine will cut steel with less than 50,000 psi and just plain water. A little lead wouldn't even have a chance.
I consider this Myth "Busted!!!"
Randy.