Now, the problem is getting the guns to Texas. If you drove there, just drive home with them. If you flew and there's too many to put in your baggage when you return, then you'll have to ship them. If you ship, then you have to abide by the shipper's rules, which probably includes that they only ship to an FFL.(a) It shall be unlawful—
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(3) for any person, other than a licensed importer, licensed manufacturer, licensed dealer, or licensed collector to transport into or receive in the State where he resides (or if the person is a corporation or other business entity, the State where it maintains a place of business) any firearm purchased or otherwise obtained by such person outside that State, except that this paragraph (A) shall not preclude any person who lawfully acquires a firearm by bequest or intestate succession in a State other than his State of residence from transporting the firearm into or receiving it in that State, if it is lawful for such person to purchase or possess such firearm in that State
If you're not going to California and just want the executor of the estate to ship the guns to you, then I don't think 18 USC 922(a)(3)(A) applies, since you're not acquiring the firearms in a state other than your state of residence. Have the executor of the estate ship the guns to a local FFL. Unless something changed recently, there is no requirement that guns being shipped from California be shipped by an FFL.