A SIG-Sauer P226 is the pistol carried by Jack Ryan (John Krasinski) during a raid in "French Connection" (S1E02). However, it appeared that he was given a SIG-Sauer P228 earlier in the episode.
SIG-Sauer P228
In "French Connection" (S1E02), Jack is given what appears to be a SIG-Sauer P228 pistol right before a raid. This pistol appears to turn into a P226 later in the episode. A P228 is also carried by Captain Sandrine Arnaud (Marie-Josée Croze).
Rifles/Carbines
Heckler & Koch HK416
The Heckler & Koch HK416 D10RS is used by members of BRI, the SWAT unit of the French National Police. CIA operatives as well as James Greer (Wendell Pierce) also use the HK416.
M4A1 Carbine
The M4A1 Carbine is carried by both soldiers as well as opposing forces. In "Pilot" (S1E01), James Greer (Wendell Pierce) uses an M4A1 to defend the CIA black site against invading forces.