Best grit for blasting?

Hey. Couple of questions here and I can't seem to search to find the answers. I work at a sand mine. You hearts right lol. I have access to as much sand as I want this stuff ranges from pretty much dust all the way to 20 grit. Now what kind of sand should I use to blast panels? I have heard sand is hats on the panels. But with a limited Budget and the proper tools/ know how is it fine to use? What do most guys use in their own shops? I know this aid could work for intakes and heads. But the body is a different animal all together. Should I buy the proper blasting media or am I done with the sand? Sorry for the newbie questions. Thanks in advance guys. -Billy