Equip the Sirin 9mm:

Once you’ve purchased the bundle, go to Call of Duty Black Ops 6 Bot Lobbies your loadout and select the Sirin 9mm from the Special Weapons tab.

Equip it in your secondary weapon slot.

Modify and Save:

Customize the weapon in the Gunsmith if desired, and then save the loadout.

Use the Sirin 9mm in-game:

You can now use the Sirin 9mm in Zombies, Warzone, and Black Ops 6 Multiplayer (if not restricted).

By purchasing the bundle, you'll be able to access the Sirin 9mm early and gain additional cosmetic rewards.

Conclusion:

If you prefer not to wait for the community event to unlock the Sirin 9mm, Method 2 (paid bundle) is the easiest and most reliable way. However, the bug method (Method 1) might still work in Zombies and cheap BO6 Bot Lobbies Warzone if you’re quick enough, though there’s a risk it could be patched soon.

To unlock the Sirin 9mm early through a paid method, you can purchase the Cash Bandit Bundle. Here's how you can do it: