The following firearms are used in the anime film Porco Rosso:
Smith & Wesson Schofield
Curtis uses a Smith & Wesson Schofield revolver.
Colt Single Action Army
Several pirates carries the Single Action Army revolvers.
Webley Mk VI
The Webley Mk VI revolvers uses by several pirates.
One of the pirates that confronts Porco and Fio carries a Mauser C96.
A several pirates carries the Haenel-Schmeisser MP28/II submachine guns.
Short Magazine Lee-Enfield (SMLE)
A few of the pirates carry SMLE rifles.
A few of the pirates carry Mauser rifles with turned-down bolt handles. This however cannot be precisely identified.
One of the pirates carries the Maxim MG08 machine gun.
Custom MG08 Maxim (Aircraft Pattern)
Porco purchases a Aircraft Pattern MG08 Maxim with a custom barrel jacket.
Several Maxim M1910 machine guns are seen mounted on fighter planes throughout the film.
Madsen machine gun
One of the pirates carries a Madsen machine gun.
Aircraft Mounted Lewis Gun
One of the pirate planes is outfitted with a Aircraft Mounted Lewis Gun.
Infantry Lewis Gun
A several pirates carries the Infantry Lewis Guns.
Model 24 Stielhandgranate
One of the pirates is seen carrying several Model 24 hand grenades.
A large cannon which appears to be a very chunkily-rendered Solothurn S-18 20mm Anti-Tank Rifle given the stock, sight and side-loading, appears mounted on one of the pirates' planes. It loads using some kind of stripper clip arrangement rather than its usual box magazine, and the barrel and rounds are scaled up to the point it resembles a small tank gun.