ORIGINAL: Rob/PA Bowyer
Are you talking about Celotex?
It certainly stops arrows and will last a very, very long time but it does leave residue on some arrows that's tough to scrape off.
If your not talking Celotex, please expound.
One of the clubs I used to shoot at used Celotex target butts.... You are right, you would play hell scraping the residue off of carbon arrows, although aluminum wouldn't pick up the residue like the carbons.