At one time there was a well pubishlized and documented test where"compressed AIR" was used to push jacketed bullets through a bbl at high velocity... After something like 80,000 rounds (yes, eighty thousand) there still wasn't any appreciable wear on the bbl.

I'm not the only one who remembers this test, and it was talked about on this site not so awfull long ago...

You are confuseing "heat" and "powder friction" wear, when i said BULLET wear....

Shooting shotshells in a rifled bbl will not hurt the rifleing, it will lead it all up and have awfull patterns though...

Drilling Man