The only thing that will help him is the ability to show that he is operating under the exemption which allows transportation directly between his home and the range. For all the good an FPIC will do, he may as well show his social security card.
If you are stopped riding a motorcycle and you present a DL without a motorcycle endorsement, do you think you'll avoid prosecution because you have shown that you can drive "some" vehicle?
If it makes you feel better to imagine what offenses a cop might make up out of thin air and try to come up with a way to protect yourself from those by pretending documents have properties that they do not actually have, who am I to stop you?
However, for the rest of the people reading this: Possession of neither a handgun nor hollowpoint ammunition is excused by the possession of an FPIC.
I also carry my FPIC all the time, but that is in case I want to use it for it's actual purpose. i.e. buying a long gun, buying pistol ammo or renewing my driver's license.