The Detective is Already DeadThe Detective is Already Dead - Internet Movie Firearms Database - Guns in Movies, TV and Video GamesThe Detective is Already Dead
A Flintlock Pistol is seen with Yui Saikawa in "What I See in That Eye".
M1911A1
A M1911A1 is seen in a flashback with Kimihiko Kimizuka in "I Still Remember, After All This Time". From "What I See in That Eye", Kimihiko is seen with it as his personal sidearm in cases when violence is expected in a case.
SIG-Sauer P365 SAS
Yui Saikawa uses what appears to be a SIG-Sauer P365 SAS in "What I See in That Eye".
Revolvers
Colt Python
A Colt Python is seemingly used with Siesta in "With That, We Set out on a Journey Once Again".
Submachine Guns
Heckler & Koch MP5K-PDW
A Heckler & Koch MP5K-PDW is seen with Charlotte Arisaka Anderson aka Char as her preferred weapon.
Rifles
AK rifle
An armed man in "I Still Remember, After All This Time" is seen armed with an AK-based assault rifle. There's not enough details to make out the specifics.
Brown Bess Flintlock Musket
A silver Brown Bess Flintlock Musket is used by Siesta, which is made to fire special ammo. She first uses it to engage Albert Coleman aka Bat in "Attention Passengers: Is There A Detective on Board?".
Winchester carbine
A Winchester-type carbine is seen inside Yui's mansion in "What I See in That Eye".
Sniper Rifles
Barrett M82A1M
A Barrett M82A1M is used by Char to snipe at Chameleon in "A Light in the Midst of Hope".
Machine Guns
Dual Machine Guns
A couple of machine guns mounted on Siesta's mech is seen in "Crimson Devil, Ice Queen".
Hand Held M134 Minigun
The Hand Held M134 Minigun is used by Char when she provides fire support for Kimihiko in "A Light in the Midst of Hope".
Others
Crossbow
A crossbow is seen in "What I See in That Eye" with a hooded assassin in a stadium.