I come down firmly on the side of
thou shall not kill. That's about it. Someone should be able to own a gun for whatever reason they want to but they shouldn't use it to kill anyone. But more on point:
Luk 22:35 And He said to them, “When I sent you without money bag, knapsack, and sandals, did you lack anything?” So they said, “Nothing.”
Luk 22:36 Then He said to them, “But now, he who has a money bag, let him take it, and likewise a knapsack; and he who has no sword, let him sell his garment and buy one.
The meaning of that is that at first they weren't sent out very far, only within Israel. But now they were being sent farther away so they would need to take provisions with them for the longer journey, including a sword. Flavius Josephus wrote of the Essenes:
For this reason they make trips without carrying any baggage at all—though armed on account of the bandits.
When they traveled they carried swords for self defense.