The Glock 17 is a prominent handgun seen in the series.
Baikal IJ-70 (Makarov PM Import)
A Baikal IJ-70 pistol is used in "The Long Way Down Job" (S4E01).
M1911A1
In "The 10 Li'l Grifters Job" (S4E02), an M1911A1 is used by Detective Ray Hammett (Steven Flynn) to threaten Nate. In a flashback to World War II, an American officer (portrayed by Christian Kane) is seen using the M1911A1 in "The Van Gogh Job" (S4E04).
Rifles
M1 Carbine
A late War model M1 Carbine is seen during a flashback to WWII in Europe in "The Van Gogh Job" (S4E04).
M1 Garand
M1 Garand rifles are carried by American Soldiers seen during a flashback to WWII in Europe in "The Van Gogh Job" (S4E04). These have the external screw on Blank Firing adapters.