During the shootout at Colby's home, Bob Lee uses a bolt action sniper rifle that resembles a Desert Tactical Arms Stealth Recon Scout in "Sins of the Father" (S3E03).
"Black King" (D&L MR-30 PG)
The customized "Black King" .338 Lapua Magnum rifle seen in the series' first two seasons makes a return appearance as Swagger uses it to take aim while above the Bama Cattle facility in "The Red Badge" (S3E08). Bob Lee uses the rifle that was winterized in "Red Light" (S3E13). In reality, the rifle is a D&L MR-30 PG.
McMillan CS5
The McMillan CS5 is used by Red Bama in "Red Light" (S3E13).
Modern Outfitters MC7
Swagger continues to use the Modern Outfitters MC7 in 7.62x51mm he had used in Season 2. In "A Call to Arms" (S3E05), Bob Lee uses the rifle to take target practice and Julie specifically ID's the rifle as an "MC7".
Remington Mk 13
The Remington Mk 13 is seen with Red Bama Sr. and Red Bama Jr. in "The Red Badge" (S3E08).
Winchester Model 70
A modern Winchester Model 70 is taken by Bob Lee from a truck and used against mercenaries in "Red Light" (S3E13).
Rifles/Carbines
AKM
The AKM is seen used by Viet Cong fighters in "Sins of the Father" (S3E03).
AKS-47
An AKS-47 is used by Major Raymond Brooks (Chad Michael Collins) of the 5th Special Forces Group during a Phoenix operation in Cambodia in "The Red Badge" (S3E08).
Colt LE Carbine
What appears to be a Colt LE Carbine is seen with a Beckett County Sheriff Deputy in "Backroads" (S3E01).
Colt Sporter I Carbine
In "Sins of the Father" (S3E03), a member of Swagger's Long Range Recon squad in Vietnam carries what appears to be a Colt Sporter II Carbine.
Colt M4A1
Colt M4A1 Carbines are seen in the hands of Atlas operatives in "Swing Vote" (S3E07) and in "Family Fire" (S3E11). FBI SWAT carry the M4A1 in "Alpha Dog" (S3E09) and "Family Fire" (S3E11). In "Red Light" (S3E13), a MPDDC officer has one with Julie Swagger using the M4A1 against mercenaries during the raid on the Swagger farm.
Colt M16A1
Members of Earl Swagger's LRRP team in Vietnam carry the M16A1 in "Sins of the Father" (S3E03). Swagger and other recruits in an intelligence training program are seen trying to assemble the rifle in the same episode.
Mk 18 Mod 0
A Mk 18 Mod 0 appears to be seen in "Swing Vote" (S3E07), "Family Fire" (S3E11) and in "Red Light" (S3E13).
Modern Outfitters MC6
The Modern Outfitters MC6 is seen with Jason Colby (Tom Wright) in "Sins of the Father" (S3E03). A similar rifle is used by Johnson in "The Importance of Service" (S3E04) and then used by Carlita Cruise (Felisha Terrell) in "Lines Crossed" (S3E06).
During a flashback, a young Bob Lee is seen armed with a Sporter Pattern 1914 Enfield while hunting with his father in Season 3's premiere "Backroads" (S3E01) and in "A Call to Arms" (S3E05).
SKS
An SKS rifle is seen in the hands of one of Earl Swagger's men in "Lines Crossed" (S3E06).
Daniel Defense M4A1
What appears to be the Daniel Defense DDM4 "M4A1" is used by Atlas operatives in "Backroads" (S3E01). DDM4 carbines also are used by mercenaries in "Red Light" (S3E13).
Daniel Defense DDM4 MK18
The Daniel Defense DDM4 MK18 appears to be used by Atlas operatives who confront Bob Lee in "Sins of the Father" (S3E03). DDM4 MK18 carbines also are used by Prosada (Juan Javier Cardenas) and his mercenaries in "Red Light" (S3E13).
Charleville 1766
What appears to be a Charleville 1766 flintlock musket is displayed in the office of Red Bama Junior (Eric Ladin) in "Red Meat" (S3E02).
A Beretta 92FS is used by Atlas operatives in Season 3's premiere "Backroads" (S3E01) and with an armed driver in the same episode. In "Red Meat" (S3E02), Spanish-speaking robber sticks up a convenience store with the Beretta. A security guard in a psychiatric hospital uses it at the end of "Swing Vote" (S3E07). In "Alpha Dog" (S3E09), Red Bama (Gerald McRaney) uses the Beretta to threaten Bob Lee. Harris Downey (Jesse Bradford) is given a Beretta and handles the pistol in "Patron Saint" (S3E12).
Beretta Model 70
Earl Swagger and a young Guiterrez are armed what appears to be suppressed Beretta Model 70 pistols during a mission in "Lines Crossed" (S3E06).
Colt Government Model
A Colt Government Model is used by Julie Swagger (Shantel VanSanten) as her sidearm in the season. A similar pistol was carried by Bob Lee's father Earl Swagger (Derek Phillips) in Season 3's premiere "Backroads" (S3E01). It appears to be seen in a stash by Nadine in "Red Meat" (S3E02).
Colt M1911A1
A Colt M1911A1 is seen used by a young Guiterrez (Michael Ocampo) to wound himself in "Lines Crossed" (S3E06). A young Raymond Brooks (Chad Michael Collins) also carries an M1911A1 when he was in the Vietnam War in "The Red Badge" (S3E08). Bob Lee uses his M1911A1 pistol to threaten Ray Brooks (Michael O'Neill) in "Family Fire" (S3E11).
Custom Colt M1911A1 (USMC)
In "The Red Badge" (S3E08), Earl Swagger threatens a young Raymond Brooks with a customized M1911A1-type pistol. The .45 is customized with raised adjustable sights and the USMC logo on the grips and a larger slide safety. This pistol also appears to be the one retrieved from a safe and loaded by Julie Swagger (Shantel VanSanten) in "Orientation Day" (S3E10). Possibly intended to pass for the original M45 MEU(SOC) pistol, which has similar (though not identical) medallions on its grip panels.
FN FNP-45 Tactical
An FN FNP-45 Tactical is used by an Atlas operative in "Sins of the Father" (S3E03). This pistol is also handled by Carlita (Felisha Terrell) in the same episode. Swagger takes it from an Atlas agent in "A Call to Arms" (S3E05).
Glock 17
A Glock 17 is carried by Isaac Johnson (Omar Epps) in the season. It's also carried by law enforcement officers/agents. In "Family Fire" (S3E11), Ray Brooks (Michael O'Neill) takes a Glock off an FBI SWAT agent. Glock 17 pistols are also used by USSS agents who confront Nadinein "Patron Saint" (S3E12).
Glock 17 (TTI Combat Master Package)
Bob Lee takes a Glock 17 (TTI Combat Master Package) from Carlita's arsenal in "Alpha Dog" (S3E09). Later in "Orientation Day" (S3E10) is used by Bob and Isaac.
Glock 26
What appears to be a Glock 26 is handled by Carlita Cruise (Felisha Terrell) in "Sins of the Father" (S3E03). Both Margo and Nadine use Glock 26 pistols in the season.
Heckler & Koch USP
A Heckler & Koch USP is stashed in an ammo box that Solotov digs up in Season 3's premiere "Backroads" (S3E01). He attempts to use it against Bob Lee, only to discover it is unloaded. Salinger (Brian Letscher) is somehow seen with it in a continuity error in "Sins of the Father" (S3E03) instead of the P226R. An Atlas operator is seen with the USP in his tac holster in "The Importance of Service" (S3E04). Several Atlas recruits are also armed with the USP in "Orientation Day" (S3E10). Both Bob Lee and Isaac attempt to use the USP, but discover that the pistols are only loaded with blanks.
Heckler & Koch HK45
A Heckler & Koch HK45 is seen held by August Russo (Raymond J. Barry) in "Orientation Day" (S3E10). This pistol is later seen in the hands of both Bob Lee and Carlita in the episode.
Heckler & Koch VP9
Bob Lee uses an Heckler & Koch VP9 in "Red Light" (S3E13). An VP9 is seen being processed at a crime scene in "Family Fire" (S3E11).
In the Line of Fire Composite Pistol
An assassin pistol made of composite materials is used in "Swing Vote" (S3E07) by Atlas assassin John Wheeler (Matt Shallenberger). The episode strongly implies that it was made from 3D-printed parts. This particular pistol bears a strong resemblance to the composite pistol that was used by John Malkovich's character in the 1993 film In the Line of Fire.
Kahr K9
Nadine is seen armed with a blued Kahr K9 in "Sins of the Father" (S3E03).
SilencerCo Maxim 9
The integrally-suppressed SilencerCo Maxim 9 is the handgun used by Atlas agents disguised by officers in "Lines Crossed" (S3E06). The pistol also is used by Swagger, who identified the pistol as a "Maxim 9" and questions if this was standard issue for DC officers.
SIG-Sauer P226R
The SIG-Sauer P226R is used by Salinger (Brian Letscher) in "Sins of the Father" (S3E03). Harris Downey (Jesse Bradford) is forced to use the pistol that he took off an Atlas operative in the episode.
SIG-Sauer P229R
A federal marshal is seen wielding a SIG-Sauer P229R pistol when he confronts Bob Lee in "Red Light" (S3E13).
Smith & Wesson M&P Shield
The Smith & Wesson M&P Shield that was used in Season 2's finale by both Bob Lee and Solotov continues to be seen in Season 3's premiere "Backroads" (S3E01).
Walther P99
At the beginning of "Lines Crossed" (S3E06), Guitierrez (Tony Plana) is seen holding a Walther P99 during a confrontation with Swagger and Johnson on the bus.
Wilson Combat Vickers Elite
In "Red Meat" (S3E02), Bob carries a Wilson Combat Vickers Elite as his usual sidearm and is seen using it throughout Season 3.
In "Red Light" (S3E13), a mercenary pulls out what appears to be a Smith & Wesson Model 629 snub revolver when he confronts a wounded Julie.
Taurus Model 85
Poole is armed with a Taurus Model 85 in "The Importance of Service" (S3E04).
Submachine Guns
Intratec TEC-9
An Intratec TEC-9 is seen with Solotov in "Backroads" (S3E01) when he breaches the BC Sheriff's roadblock.
Smith & Wesson M76
In "Sins of the Father" (S3E03), a Smith & Wesson M76 is seen carried by Earl Swagger while in Vietnam in 1969. He continues to carry it while working for the Phoenix Program.
SIG-Sauer MPX
The SIG MPX are seen with Maxim Defense CQB Stock, Trijicon MRO and suppressor are seen carried by Atlas mercenaries in "The Red Badge" (S3E08).
Machine Guns
M60
The M60 is carried by a member of Earl Swagger's squad in Vietnam in "Sins of the Father" (S3E03).
Johnny Poole (Billy Lush) is seen holding an Ithaca 37 shotgun in "Red Meat" (S3E02). Bob Lee later takes the shotgun and empties the shells in the episode.
Ithaca 37 (Short)
What appears to be an Ithaca 37 with a pistol grip seen at the right in the cabin in "Sins of the Father" (S3E03).
Winchester Model 1200
A Winchester Model 1200 shotgun is seen with a member of Earl Swagger's squad during the recon op in Vietnam in "Sins of the Father" (S3E03).
12 Gauge Double Barreled Shotgun
A 12 Gauge Double Barreled Shotgun is seen in the hands of the man guarding Red Bama Jr. in "The Red Badge" (S3E08). This shotgun is also handled by Bob Lee in the episode.
Grenades
Model 7290
The Model 7290 is seen inside a bag in "Red Meat" (S3E02).
M26 Hand Grenade
In "Sins of the Father" (S3E03), several M26 hand grenades are seen carried on Earl Swagger's pack while in Vietnam.
M67 Hand Grenade
An M67 Hand Grenade is seen in "Patron Saint" (S3E12) in Wheeler's safe and in a booby-trapped door.
M83 Smoke Grenade
Several M83 smoke grenades are strapped to the transmitter carried by a member of Swagger's LRRP squad in "Sins of the Father" (S3E03).
A Milkor M32 MGL is seen in the hands of a mercenary in "Red Light" (S3E13).
Arsenals
Gun Rack
A gun rack is seen in the sheriff's office in "Backroads" (S3E01).
Carlita's Arsenal
Carlita Cruise puts an arsenal of weapons in an office room seen in "Alpha Dog" (S3E09). Bob Lee is seen taking a pistol from this arsenal in the episode.