DO NOT DO WHAT YOU ARE SUGGESTING. IT IS MOST DEFINITELY ILLEGAL.
On every firearm made, pretty much for the past 111 years, there exists one "part" that carries the serial number of the gun. This part is, for the relevant legal purposes, the firearm itself. Shipping that in interstate commerce in order to effectuate a transfer of ownership between two people, even if each could legally otherwise own the gun, is illegal when done between individuals who do not hold Federal Firearms Licenses.
Don't get cute with this and think you can save $20 or $25 bucks per gun avoiding the fee you'll likely have to pay a local FFL to receive the guns for you.
ALSO, since you are only 18 years old, a dealer will not be able to transfer a handgun to you. TX allows you to own one at 18, but not to buy one from a dealer.
(ATF Online - Publication 5300.5: State Laws and Published Ordinances - Firearms)
Nice, quick, and readable summary:
GunBroker.com Support FAQ 1118 : Firearms Shipping Guide
Shipping Legalities Federal Law requires that all modern firearms be shipped only to a holder of a valid Federal Firearms License (FFL). The recipient must be have an FFL; however the sender is not required to have one. Any person who is legally allowed to own a firearm is legally allowed to ship it to an FFL holder for any legal purpose (including sale or resale). Here is exactly what the ATF 'Federal Firearms Regulations Reference Guide' (ATF P 5300.4) says:
(B8) May a nonlicensee ship a firearm by common or contract carrier?A nonlicensee may ship a firearm by a common or contract carrier to a resident of his or her own State or to a licensee in any State. A common or contract carrier must be used to ship a handgun. In addition, Federal law requires that the carrier be notified that the shipment contains a firearm and prohibits common or contract carriers from requiring or causing any label to be placed on any package indicating that it contains a firearm.
[18 U.S.C. 922(a)(2)(A), 922(a) (3), 922(a)(5) and 922(e), 27 CFR 478.31 and 478.30]
(B7) May a nonlicensee ship a firearm through the U.S. Postal Service?[A nonlicensee may not transfer a firearm to a non-licensed resident of another State. A nonlicensee may mail a shotgun or rifle to a resident of his or her own State or to a licensee in any State. The Postal Service recommends that long guns be sent by registered mail and that no marking of any kind which would indicate the nature of the contents be placed on the outside of any parcel containing firearms. Handguns are not mailable. A common or contract carrier must be used to ship a handgun.
[18 U.S.C. 1715, 922(a)(3), 922(a)(5) and 922 (a)(2)(A)]
For god's sake, if you have to ask legal advice on an internet forum please at least make it a forum somewhat related to the topic at hand.
I don't ask members of the TheFiringLine Crossfire questions, and I sure as hell wouldn't risk federal firearms charges by relying upon permissive firearms shipping advice I received from a car forum.
I know it is "rude" to use large fonts, but if not now, when?
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And yes, I Am A Lawyer but I'm not your lawyer. Nothing contained in this message counts as legal advice. You are not my client and I am not bound by lawyer client privilege. I am not admitted to the practice of law in TX, only NY.