A tu-tone Heckler & Koch USP was used by Daniel Graystone (Eric Stoltz) and the Zoe Avatar in the U-87 Cylon body in Season One, Episode Seven, "Ghosts in the Machine."
Walther P38
In Season One, Episode Seven, "Ghosts in the Machine", Heracles is seen carrying a Walther P38 into New Cap City. Joseph Adama calls it a "small gun."
Colt Python
A pair of Colt Python revolvers are carried by Joseph Adama and Emmanuelle into the burlesque club in Season One, Episode Seven, "Ghosts in the Machine."
Smith & Wesson Model 10
Webley Mk VI
Smith & Wesson Schofield
Ruger P85
FN Five-SeveN
Seen in the hands of Caprica City spaceport police officers.
Submachine Guns
MP-40
An MP40 is seen inside the arms locker of the burlesque club.
Kimel AP-9
A Kimel AP-9 is carried by Joseph Adama (Esai Morales) into the burlesque club in the V-world game "New Cap City".
KGP-9
A Hungarian KGP-9 carbine being repeatedly stripped and re-assembled by the Zoe Avatar in the U-87 Cylon body in Season One, Episode Seven, "Ghosts in the Machine." It has been dressed up by the show's armorers to resemble a weapon consistent with the Cylon design aesthetic.
Heckler & Koch MP5A3
Several Heckler & Koch MP5A3 submachine guns were carried by Global Defense Department operators in news footage in Season One, Episode Two, "Rebirth."
Sten Mk II
Skorpion machine pistol
Sterling L2A3
Sterling L2A3 sub-machine guns were seen in the of players in the V-world game New Cap City. Sterling L2A3s were also seen in the hands of Soldiers of the One guards protecting the Church on Gemenon.
Thompson M1928
Seen in the hands of Daniel Graystone (Eric Stoltz) while in the V-World.
Assault Rifles
L85A1
An L85A1 can be seen in the hands of a Caprican police officer at the memorial to the maglev bombing in the Season One, Episode One, "Rebirth." The L85A1 was previously shown in Battlestar Galactica to be the standard-issue assault rifle of the Colonial Armed Forces with L85A1's being seen in the hands of a Colonial Fleet honour guard at Zak Adama's funeral in Season 1 and in the hands of Samuel Anders' resistance fighters on Caprica in Season 2.
M4A1 carbine
Seen among the numerous rifles at the Soldiers of the One training camp.
Rifles
Winchester Model 1894
Sniper Rifles
During the climactic scene in the finalé, Cylon Marine snipers take out monotheistic terrorists.