Throughout the series, Robert McCall (Edward Woodward) carries as his sidearm the Walther PPK/S. McCall always cleanly dispatches his foes with one well placed shot usually after giving them some chance to surrender.
Walther PP
McCall carries a Walther PP as his sidearm in the pilot episode "The Equalizer" (S1E01).
Browning BDA
In "Torn" (S1E17), McCall is seen taking what appears to be a Browning BDA from a thug and uses it in the arms warehouse shootout.
Browning Hi-Power
The Browning Hi-Power is seen throughout the series. The pistol briefly seen in the hands of a mob guard in "The Confirmation Day" (S1E06).
Colt M1911A1
The M1911A1 is used by various characters throughout the series. In "Out of the Past" (S1E08), Michael Rosa (Jon DeVries) carries a suppressed M1911A1 as his weapon of choice. McCall is seen holding it on him in the episode. In Season 1 "Dead Drop" (S1E15), Ginger (Robin Curtis) carries an M1911 fitted with a suppressor and scope.
Desert Eagle Mark I
The Desert Eagle Mark I is a frequent weapon of McCall's throughout the series.
Detonics CombatMaster
In "Desperately" (S1E11), Geoffery Dryden (Ray Sharkey) is seen carrying what appears to be a stainless Detonics CombatMaster in an ankle holster. He is seen using the pistol mainly with a suppressor.
Heckler & Koch VP70Z
In "Breakpoint" (S1E19), Tony Shalhoub carries a Heckler & Koch VP70-Z as the leader of a terrorist cell that takes over the wedding reception that McCall was attending.
Smith & Wesson Model 639
In "No Conscience" (S1E20), McCall is seen loading a stainless steel version of the Smith & Wesson Model 639. The magazine is clearly a single stack magazine. McCall only uses the pistol as a decoy for the bad guys to find. After finding the Smith the evil doers assume McCall is unarmed, McCall then reveals his trusty PPK is in an ankle holster which he uses to dispatch two of the villains.
Taurus PT92
In "Out of the Past" (S1E14), a Taurus PT92 is seen being handled by Walter Wesley (Barry Primus), who says, "this thing, no matter whether I know how to use it or not, makes me less scared". This pistol has the curved trigger guard and has no safety selector on the frame. Because this episode was filmed in the early 1980's, this is likely one of the earliest appearances of this pistol in a feature film or television series.
Tokarev TT-33
In "Unpunished Crimes" (S1E21), Frank Donahue (Dan Hedaya) removes a Tokarev TT-33 from a foot locker along with several medals from his service in the Vietnam War. McCall identifies it as a Tokarev 7.62mm that was liberated and advises Donahue against using it to commit suicide because "that ammunition is notoriously unreliable" and may not finish the job.
.22 Long Rifle Pen Gun
In Season 1's "Breakpoint" (S1E19), the NYPD tries to smuggle a .22 Long Rifle Pen Gun to McCall. The head terrorist (Tony Shalhoub) discovers the Pen Gun and discharges it at the officer disguised as a doctor.
Revolvers
Colt Python (Snub)
Mickey Kostmeyer (Keith Szarabajka) is seen carrying a Colt Python snubnose in several episodes, notably "Breakpoint" (S1E19).
Smith & Wesson Model 10
The Smith & Wesson Model 10 is seen in many episodes as the standard sidearm for officers of the NYPD. Officer Sandra Stahl (Karen Young) carries one as her duty weapon in Season 1's "Lady Cop" (S1E05).
Smith & Wesson Model 29
In "Bump and Run" (S1E10), a vigilante who passes himself off as the Equalizer uses a Smith & Wesson Model 29 with a 8 3/8" barrel as his weapon of choice. An NYPD detective describes the weapon as a .44 Magnum loaded with hollow points.
Smith & Wesson Model 36
In the pilot episode "The Equalizer" (S1E01), a government agent is seen with a Smith & Wesson Model 36.
Smith & Wesson Model 60
In "The Confirmation Day" (S1E06), a mobster appears to be armed with a Smith & Wesson Model 60.
Colt Detective Special (Nickel)
In "Lady Cop" (S1E05), Officer Nick Braxton (Will Patton) is seen using a nickel Colt Detective Special when taken out of the purse of Officer Sandra Stahl. He also pulls the revolver on McCall in the episode.
Taurus Model 85
In Season 1's "Desperately" (S1E11), McCall is seen taking a Taurus Model 85 from Macklin (David Marguiles).
Shotguns
Remington 870
McCall uses a Remington 870 modified with a laser sight during an early version of a shoot/don't shoot simulator in "Reign of Terror" (S1E12).
Ithaca 37
The riot model of the Ithaca 37 is seen wielded by NYPD officers and various bad guys. In "The Defector" (S1E03), one can also be seen with a pistol grip in McCall's private weapons cache as well as used by several Russian operatives.
Franchi SPAS-12
A Franchi SPAS-12 can be seen in McCall's secret cache of weapons in "The Defector" (S1E03).
Winchester 1897 Shotgun
In the pilot episode "The Equalizer" (S1E01), a gunman opens fire on McCall's Jaguar with a Winchester Model 1897.
The Heckler & Koch HK94 with the barrel chopped down to resemble the MP5A3 is another weapon frequently seen in the series. The man in the Red Parka is seen with one in "Dead Drop" (S1E15). This also is likely one of the earliest appearances of the firearm in a US television series.
Rifles
M1 Carbine
McCall uses an M1 Carbine on hitmen after a car chase in the pilot episode "The Equalizer" (S1E01).
Galil AR
A Galil assault rifle is seen in "Dead Drop" (S1E15).
Mauser 660 Sniper Rifle
Mickey Kostmeyer (Keith Szarabajka) uses what appears to be a takedown version of the Mauser 660 rifle fitted with a scope and suppressor in Season 1's "Dead Drop" (S1E15). McCall uses the rifle in "Wash-Up".
AK Series
AKMs, both underfolder and fixed stock, can be seen in the hands of Warsaw Pact soldiers in "Torn" (S1E17).
Ruger Mini-14
In "The Children's Song" (S1E07), a Ruger Mini-14 is seen used by both Dillart (Bradley Whitford) and Ray (William Youwans). The rifle is later seen used by both McCall and his son Scott (William Zabka).
Ruger Mini-14 GBs are also seen in the hands of the NYPD ESU teams in "Torn" (S1E17).
Steyr SSG 69
In "Dead Drop" (S1E15), a Steyr SSG 69 appears to be the rifle held by one of the Dead Drop associates (Robert O'Reilly).
Other
Riot Gun
In "The Defector" (S1E03), Stock uses a riot gun to launch a smoke grenade.
McCall's Hidden Arms Cache
In "The Defector" (S1E03), McCall is seen keeping several weapons hidden behind workshelves in his workshop.
Gun Dealer's Cache (Rambo's Survival Knife)
In "Out of the Past" (S1E14), a street arms dealer shows off a cache of weapons for Eddie Washburn (Stephen McHattie) to choose from to purchase. When Washburn says he can't afford $500 for an illegal gun, the dealer offers Rambo's Survival Knife as seen in First Blood for $100. The arms dealer even says, "this is made by some dude down in Arkansas", ostensibly referring to knifesmith Jimmy Lile, the designer of the First Blood knives.