Is It Jewish To Own Or Sell Guns?

Mishneh Torah, Foreign Worship and Customs of the Nations 9:8
(8) Even as it is forbidden to sell to idolaters things which uphold their hands to idolatry so it is forbidden to sell them things wherein there is a menace to the public, for instance, bears, lions, weapons, iron fetters, and chains; it is likewise forbidden to sharpen their weapons for them. And, everything which is forbidden to sell to an idolater is also forbidden to sell to an Israelite who is under suspicion that he might resell it to an idolater. It is likewise forbidden to sell instruments of harm to robbers who profess to be Israelites.

Avodah Zarah 16a:3
The Gemara clarifies: And as for the fact that nowadays we do sell all weapons, Rav Ashi said: We sell the weapons to the Persians, who protect us.

Shulchan Arukh, Yoreh De'ah 151:6
If Israel was dwelling among non-Jews, and the Jews made a covenant with their rulers, Jews may sell weapons to the king's servants and his troops, for they make war on their behalf with the enemies of the state, to save them, and it turns out they protect them, for they (the Jews) are dwelling in their midst.

Is It Kosher For Israel To Sell Arms To Other Countries?
As Israel began to develop its arms industry in the 1950s and ’60s, it became clear that the industry could not support itself (and therefore provide the IDF with necessary weapons) unless it also exported these powerful products. As Amir Bohbot and Yaakov Katz document in The Weapon Wizards, this trade also spawned a significant financial boom to a fledging country with economic struggles while providing important incentives for foreign countries to develop friendly relations with Israel. Yet it also raised deep ethical questions, as clients like Chile and South Africa committed human rights atrocities.
In the late 1970s, Tel Aviv chief rabbi Chaim David Halevi cited medieval precedents to argue that any sales made to allies would secure mutually beneficial results, even while noting that Israeli sovereignty placed Jews in a radically different political position. Rabbi J. David Bleich reached a similar conclusion, though he indicated his uncertainty as to whether current Israeli policy fully complied with halachic criteria: “Sale of arms to nations allied with Israel by means of a formal or informal security pact would be justified. Absent such agreement, arms sales would be forbidden unless absolutely necessary by virtue of other considerations in order to protect life, e.g., as part of a barter arrangement designed to secure material necessary for self-defense.”
Because of reported sales to rogue nations with unethical leaders, other scholars raised serious objections to the Israeli arms industry in the early 1980s. Rabbi Yehuda Gershuni contended that international arms sales could be justified only when they involved nations that had Jewish citizens to protect or would adhere to principles of ethical warfare. Otherwise, Israel was providing a “stumbling block” that encouraged unethical behavior by aiding and abetting rogue nations. The fact that these countries could purchase weapons from other dealers could not justify any Jewish participation in the shedding of blood, especially if the Israeli weapons were deemed uniquely advantageous.
The most trenchant critique was launched by Britain’s chief rabbi Immanuel Jakobovits. He accused Israel, Britain, the United States and other Western countries of greedily following the ways of the biblical Esau. In his words, “The rationalization that such exports are required to sustain the supply-nations’ own arms industry for self-defense lacks every moral basis, at least in Jewish teaching. You can never save your own life at the cost of threatening or taking another.”
Rabbinic defenders of the Israeli arms industry have responded that even when mistakes are made, the Talmudic and medieval precedents fully legitimize selling weapons to foreign nations if the goal is to buttress Israel’s own defense. Although military exports bring Israel into murky moral waters, they are a tragic part of the complexity of foreign affairs in a world in which swords, not plowshares, continue to hold sway.
In the particular case of Myanmar, it remains hard to understand what financial, diplomatic, or military advantage is procured from selling weapons to this insignificant country while it is in the midst of a horrific civil conflict. Jewish law reluctantly permits weapons sales when they produce concrete security advantages, but not when meager benefits are greatly overshadowed by aiding horrific bloodshed. I join Rabbi Yuval Cherlow in calling for expanded ethical overview of such sales to ensure that Israel properly balances its strategic needs and moral duties.

"Jews and Guns" My Jewish Learning
https://www.myjewishlearning.com/article/hunting-in-judaism/
Most authorities say it is not permissible to hunt for sport. Two sources are generally cited in this regard. The first is Rabbi Isaac Lampronri, who wrote in his work Pahad Yitzhak that it is forbidden to hunt animals because it’s wasteful. The 18th-century rabbinic authority Ezekiel Landau added that recreational hunting is forbidden on the grounds of animal cruelty and because of the risks to the hunter. Neither of the two biblical figures known to be hunters — Esau and Nimrod — are held up as role models. All the biblical patriarchs (Abraham, Isaac and Jacob), as well as Joseph, Moses and King David were herders — nurturers of animals, not their pursuers.
Hunting for food is, in principle, not objectionable. However land animals must be ritually slaughtered by hand to render them kosher , which would make hunting them for food with a firearm impermissible.