Assuming you have current license plates on the car and drive the speed limit, what's to worry? I haven't been pulled over for anything other than a speeding ticket in 20 years. Don't go getting paranoid.

A funny story though - this happened thirty six years ago. I was active duty at the time and being transferred from CA (pre-anti gun craziness) to Missouri to go to grad school. I had an old Bronco that was loaded with some household things and a wooden crate loaded with my rifles and pistols in the back. I also had my Ruger 44mag under the seat. I was spending a few days with old friends at the Gold Miner in Eldora Colorado which is up the canyon out of Boulder. My friend and I had gone into Boulder for dinner or something (hey it was over 30 years ago) and were driving back to Eldora. I was young and we were hotfooting it up the mountain. My Bronco was carbureted (what fuel injection?) for sea level and would backfire loudly if you backed off from full throttle. We got up to Nederland and stopped in one of the bars to get a beer before heading back to the Gold Miner. When we came out of the bar to drive back there was a police cruiser parked behind my Bronco. As we walked up I asked the officer if there was a problem. He explained that some hippies (it was 30 years ago, remember, and this was Boulder canyon) camping along the road reported being shot at by someone driving a Bronco that matched my description. I explained to the officer that I was Air Force being transferred from Sacramento to Missouri and that my Bronco was backfiring badly in the altitude from running too rich. He checked my ID then asked the fateful question, "Did I have any firearms in the Bronco?" I said I had a sealed crate with my firearms in the back and dropped the tailgate to show him an obviously sealed crate all taped up. I was keeping my fingers crossed he wouldn't ask if that was all, and he didn't. He told me to take it easy on the road going past the campground so as not to stir up the hippies again and that was it. The 44 magnum under the driver's seat hadn't been fired and was clean, but I'm sure it would have turned a five minute encounter into at least a few hours.