The main battery for the République-class ships consisted of four Canon de 305 mm Modèle 1893/96 guns mounted in two twin-gun turrets, one forward and one aft.
These guns fired a 350-kilogram (770 lb) shell at a muzzle velocity of 865 meters per second (2,840 ft/s).
At their maximum elevation of 12 degrees, the guns had a range of 12,500 m (41,000 ft).
Their rate of fire was one round per minute.
Both the turrets and the guns were electrically operated; both guns were typically elevated together, but they could be decoupled and operated independently if the need arose.
The guns had to be depressed to a fixed loading position, −5 degrees, between shots.
Ready ammunition storage amounted to eight rounds per turret.
Though earlier French battleships had carried a mix of several types of shells, including armor-piercing (APC), semi-armor-piercing (SAPC), cast iron, high-explosive, and shrapnel shells, République and Patrie standardized on a load-out of just APC and SAPC shells.
In peacetime, each gun was supplied with 65 shells, for a total of 260 per ship, of which 104 were APC and the remaining 156 were SAPC.
The wartime supply was three times that, at 780 shells in total.

The secondary battery consisted of eighteen Canon de 164 mm Modèle 1893 guns; twelve were mounted in twin wing turrets and six in casemates in the hull.
The turret guns had a maximum range of 10,800 m (35,400 ft) while the casemate guns could engage targets out to 9,000 m (30,000 ft).
They were supplied with APC and SAPC ammunition, weighing 54.9 kg (121 lb) and 52.3 kg (115 lb), respectively, and was fired at a muzzle velocity of 900 m/s (3,000 ft/s).
Their rate of fire was three rounds per minute.
As with the main battery turrets, the secondary turrets were electrically operated, though elevation was done by hand.
Unlike the main battery guns, they could be loaded at any angle.
The casemate guns were entirely hand-operated.

Though designed with a tertiary battery of twenty-four 47 mm (1.9 in) guns for defense against torpedo boats, during construction it had become clear that the gun was no longer suitable for use against the latest torpedo boats.
Accordingly, on 22 August 1905, the navy ordered that sixteen of those guns, all of which were to be mounted in the hull, be replaced with thirteen 65 mm (2.6 in) Modèle 1902 guns, which had a rate of fire of 15 shots per minute and a maximum range of 8,000 m (26,000 ft).
The remaining eight 47 mm Modèle 1902 guns, which were located in the foremast fighting top and in the forward and aft superstructure, were retained.
These guns had the same rate of fire as the 65 mm guns, but their range was less, at 6,000 m (20,000 ft).
They also fired a significantly lighter shell, 2 kg (4.4 lb), compared to the 4.17 kg (9.2 lb) shell of the larger gun.
Ammunition stowage amounted to 450 rounds per gun for the 65 mm weapons and 550 shells per gun for the 47 mm guns.

The ships were also armed with two 450 mm (17.7 in) torpedo tubes submerged in the hull, abreast the forward 164.7 mm gun turrets.
They were arranged at a fixed angle, 19 degrees forward of the beam.
Each tube was supplied with three Modèle 1904 torpedoes, which had a range of 1,000 m (3,300 ft) at a speed of 32.5 kn (60.2 km/h; 37.4 mph), carrying a 100 kg (220 lb) warhead.
Each ship carried twenty naval mines that could be laid by the vessels' pinnaces.
The main battery for the République-class ships consisted of four Canon de 305 mm Modèle 1893/96 guns mounted in two twin-gun turrets, one forward and one aft. These guns fired a 350-kilogram (770 lb) shell at a muzzle velocity of 865 meters per second (2,840 ft/s). At their maximum elevation of 12 degrees, the guns had a range of 12,500 m (41,000 ft). Their rate of fire was one round per minute. Both the turrets and the guns were electrically operated; both guns were typically elevated together, but they could be decoupled and operated independently if the need arose. The guns had to be depressed to a fixed loading position, −5 degrees, between shots. Ready ammunition storage amounted to eight rounds per turret. Though earlier French battleships had carried a mix of several types of shells, including armor-piercing (APC), semi-armor-piercing (SAPC), cast iron, high-explosive, and shrapnel shells, République and Patrie standardized on a load-out of just APC and SAPC shells. In peacetime, each gun was supplied with 65 shells, for a total of 260 per ship, of which 104 were APC and the remaining 156 were SAPC. The wartime supply was three times that, at 780 shells in total.
The secondary battery consisted of eighteen Canon de 164 mm Modèle 1893 guns; twelve were mounted in twin wing turrets and six in casemates in the hull. The turret guns had a maximum range of 10,800 m (35,400 ft) while the casemate guns could engage targets out to 9,000 m (30,000 ft). They were supplied with APC and SAPC ammunition, weighing 54.9 kg (121 lb) and 52.3 kg (115 lb), respectively, and was fired at a muzzle velocity of 900 m/s (3,000 ft/s). Their rate of fire was three rounds per minute. As with the main battery turrets, the secondary turrets were electrically operated, though elevation was done by hand. Unlike the main battery guns, they could be loaded at any angle. The casemate guns were entirely hand-operated.
Though designed with a tertiary battery of twenty-four 47 mm (1.9 in) guns for defense against torpedo boats, during construction it had become clear that the gun was no longer suitable for use against the latest torpedo boats. Accordingly, on 22 August 1905, the navy ordered that sixteen of those guns, all of which were to be mounted in the hull, be replaced with thirteen 65 mm (2.6 in) Modèle 1902 guns, which had a rate of fire of 15 shots per minute and a maximum range of 8,000 m (26,000 ft). The remaining eight 47 mm Modèle 1902 guns, which were located in the foremast fighting top and in the forward and aft superstructure, were retained. These guns had the same rate of fire as the 65 mm guns, but their range was less, at 6,000 m (20,000 ft). They also fired a significantly lighter shell, 2 kg (4.4 lb), compared to the 4.17 kg (9.2 lb) shell of the larger gun. Ammunition stowage amounted to 450 rounds per gun for the 65 mm weapons and 550 shells per gun for the 47 mm guns.
The ships were also armed with two 450 mm (17.7 in) torpedo tubes submerged in the hull, abreast the forward 164.7 mm gun turrets. They were arranged at a fixed angle, 19 degrees forward of the beam. Each tube was supplied with three Modèle 1904 torpedoes, which had a range of 1,000 m (3,300 ft) at a speed of 32.5 kn (60.2 km/h; 37.4 mph), carrying a 100 kg (220 lb) warhead. Each ship carried twenty naval mines that could be laid by the vessels' pinnaces.
République-class battleship