The shooting range guy is a prosecution witness. Nurmi objected to him being called to testify on grounds that he has watched too much media coverage of this case. The judge sided with the JM and told Nurmi that he'd be able to cross examine him.
I don't think Nurmi has anything to prove that Travis had a gun. There's NO doubt in my mind that the 25 auto used to kill Travis belonged to Jodi's grandparents.
It's about the totality.
In order;
1) On May 26th, a heated text exchange between Jodi and Travis. In these messages, Travis calls her all kinds of names and tells her that she is evil and the worst thing that ever happened to him. This is when the **** hit the fan.
2) May 28th, a 25 auto is stolen in an odd "burglary" 5 days before her murder trip. The "burglar" breaks in and finds the gun cabinet, takes the 25 but strangely leaves behind many dollars in quarters that were piled on top of this very cabinet. According to Jodi, this "burglar" stole 30 dollars from her. So if this "burglar was interested in petty cash, why leave behind all those quarters and half dollars? Moreover, valuable rifles and shotguns in their holsters are also left behind. We know this "burglar" had a napsack as evidenced by the missing DVD player and stereo system. So if this "burglar" existed, he would have had a way to carry the guns with him. So why leave them and instead take a worthless DVD player? We're talking 2008 here when DVD players were dirt cheap on average. Certainly a shotgun would command more on the black market than a DVD player. Further, this family was poor and didn't even have an HD television so we can be almost certain that the stolen DVD player was practically worthless, especially in comparison to a shotgun or rifle. Conclusion -- the burglary was staged.
This phantom burglar gives Jodi a convenient "alibi" for the missing 25 auto. This is why she did not just take it or borrow it. She knew that eventually she would have to dispose of it, and it would look even worse if detectives discovered that a 25 auto at her place of residence just vanished into thin air before the murder. Deadly weapons just don't sprout legs and walk away. Pinning the blame on a phantom burglar was necessary.
3) 25 auto is used to kill Travis. Not a very common type of gun.
Jodi disposes of said 25 auto "in the desert". This is another indication that she was the owner of the gun and not Travis. We know that Jodi tossed his camera in the washing machine to destroy the DNA and hardware circuitry. She was willing to leave behind his stuff as long as it was wiped of evidence. So it stands to reason that if this 25 really belonged to Travis, she would have tossed the gun in the washing machine too. Or at the very least, cleaned it off upstairs in the sink and left it there. But she took it with her and the most likely reason for that is because she feared that it could be traced back to her grandparents.
4) Jodi tells Flores that Travis did not have any weapons besides his fists in a recorded phone call. She had no reason to lie about this at the time. Telling her current "truth" would not have incriminated her nor would it have damaged his ego, err I mean reputation. She must have been telling the truth to Flores.
5) Jodi tells Flores in a taped interview that she didn't even know her grandparents had *guns* until the "burglary", directly contradicting what she would later say on the stand. On the stand, she says she only knew about the rifles before the burglary, but not the handgun. How is that a contradiction to what she told Flores? Simple. Jodi used the plural gun(s) not GUN. She denied knowledge of all guns! The most likely explanation for this lie is that Jodi did indeed steal the 25 from her grandparents and her guilty conscious compelled her to deny all knowledge to appear as innocent as can be.
Take it all together and it becomes PROOF that she brought the 25 auto with her.