Can i pass a background check to buy a gun while your on deferred felony probation?

You should not be able to, as your probation more than likely would show up on a background check, and to attempt to purchase a firearms, or being in possession of a firearm may be in direct violation of probation. Check with your probation officer, for it's better to ask and be told no than have the police show up at the gun shop while you're waiting for the background check to be completed. I've seen it, and it's not pretty.