YES, Long gun can be purchase across the state line but a handgun cannot be purchase out of the state line (have to be purchase in your state of residence). I hope this helps!

Rifles and shotguns yes, as long as there is no law in the state you live in prohiting you from bringing guns purchased out of state home

Paul, yes Sir. Long Guns can be purchased across State lines by Federal Law. Handguns cannot be purchased outside of your State of residence. Cheers and stay safe!