Neal Caffrey doesn't like guns. There is a reason for that, a reason Neal makes sure stays buried deep, deep in his past.
Until the day he has to decide between his secrets and Keller, and it's not really a choice after all. Peter fingers the hole in his trousers, an inch away from his thigh, but doesn't ask again.
(''Long story.'')
Fortunately.
Unfortunately for Neal, he can't afford too many lucky shots. He knows he was incredibly fortunate not to be asked about how he knows to put a gun together just well enough to pretend he's an actual assasin, or how well he can shoot at a moving target.
(''Just because I don't like guns doesn't mean I don't know how to use them.'')
He knows he probably shouldn't have made that shot, but he was angry at Peter at that time and his emotions got the best of him. And, if he has to be honest, he wanted to show off a little – he could never resist that impulse. Putting his tantrums and vanity aside, he still can't believe Peter didn't question him about it later.
When Peter offerred him full immunity for his life story, he accepted the opportunity to add a little credibility to his recently unveiled skills. He slipped half-truths and lies into the real story, just enough to avoid detection, just enough to make it believable. While it's true that he wanted to join the police ranks, his shooting skills come from somewhere else. You don't have to be a brilliant shot to be a cop.
He knows that if he keeps flaunting his gun skills, even unintentionally, eventually he's going to have to answer uncomfortable questions, and his claimed alibi may not hold. As much as he doesn't want to lie to Peter, he doesn't want to talk about his past more.
He dreads the day it comes to that.
A/N: As I wrote this, I was flirting quite heavily with the idea of explaining Neal's gun skils as Bryce Larkin's. But I didn't want to make this into a Chuck crossover, as I don't believe that there would be enough time in Neal's life for that storyline as well. That is to say, I love WC/Chuck crossovers, and that explanation is very appealing to me, so I figure in another universe it could have hapened like that.