
.308 M1A
Powerful, accurate, fairly common cartridge, reliable, and easier to maintain than other semiautomatics

.22 SIG Mosquito
extremely quiet, common cartridge, I can pick it up at my local sporting goods store, and I can fit flashlights and stuff on the rail so it's still useful even if out of ammo

Bastard sword
Good length and weight, durable, fairly maneuverable, and if it ever dulls out I could still swing it like a less-versatile bat with a good effect