Daniel is correct for Missouri residents. You may purchase a long gun and take possession that day. You may not purchase a handgun. For residents of states who limit magazine capacity this rule has some further caveats. TN dealers are now longer to transfers ANY GUNS to California residents.
It depends. To my understanding if you live out of state you can do this with a long gun but not a handgun. So if you're here to buy a shotgun or a rifle, have fun at any gun store in Tennessee. If you want to buy that Glock that's just been calling your name, you're out of luck.
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