This set of facts illustrates two issues: (1) witness credibility; and, (2) sufficiency of the evidence. I will start with your general question: "can you be convicted for attempted murder with no weapon found or ballistics done". The short answer is "Yes". A witness can testify that a defendant shot someone and if that witness is believed then a defendant can be convicted even if no gun is ever found. Think about it, if all a shooter had to do to never be convicted is to get rid of a gun, then everyone would just have to get rid of a gun and they would be conviction-proof. That does not make common sense. Also, there is a jury instruction that states that the testimony of one witness is sufficient to prove a fact if that witness is believed. This brings me to the second part of the question: is the witness credible or believable? some of those "believability" factors are: can a witness identify the shooter, did they get a good look, how certain are they, did the witness make prior statements about the identity of the shooter that are inconsistent or consistent with the witness' present testimony, are there other factors that would hinder an identification such as only a brief view of the shooter, the stress of the witness, and the list is as long as the ability of the lawyer to imagine factors that would influence a witness. Other issues: ballistics are used to show whether a projectile was fired from a particular gun or from a particular caliber of a weapon, they do not show a person possessed a particular weapon or that a person fired the weapon. Fingerprints and/or gun-shot residue would be indications of whether someone touched a weapon at some point in time and gun-shot residue would show whether someone had recently shot a weapon. All that being said, this defendant had better get a good criminal defense lawyer. If you want further information, write to my email or draft another question.
The short answer to your question is: If, after all the evidence is presented to the jury, they find the person guity...then yes he can be convicted and sent to prison. It sounds like there are some problems with the prosecution's case. However, to properly evaluate the case, I would have to see the police reports and preliminary hearing transcript to determine what evidence the prosecution is relying on to convict and what evidence the preliminary hearing judge relied upon to hold the person to answer and bind them into the trial court.