For the first three episodes, Tom Mason (Noah Wyle) is seen carrying a Norinco Type 56-1, the Chinese underfolding stock copy of the AKMS, with its distinctive hooded front sight. The rifle also appears to have duct tape wrapped around the end of the stock, presumably for relief when the rifle is put to the shoulder.
Norinco Type 56
Several resistance fighters are seen armed with Norinco Type 56 rifles.
AKM
Throughout the remainder of Season 1, Tom Mason (Noah Wyle) carries an AKM as his preferred weapon.
After having lost his M4A1 during the events of "Prisoner of War" (S1E03), Hal Mason (Drew Roy) carries a Galil MAR carbine fitted with a conventional bolt handle and top mounted rail as his preferred weapon.
M4A1 Carbine
Colt M4A1 carbine is a prominent weapon seen carried by the resistance. Several of the rifles are seen fitted with various accessories. In the first episodes, Hal Mason (Drew Roy) is seen carrying the M4A1. Among the fighters seen with the rifle are Jimmy Boland (Dylan Authors) and Mike (Martin Roach).
M16A1
An M16A1 can be seen in the hands of a resistance fighter.
M16A2
Several resistance fighters are seen armed with M16A2 rifles.
M16A4
One resistance fighter can be seen armed with an M16A4 rifle, identifiable by the removable carry handle/rear sights.
A rifle of the Heckler & Koch pattern can be seen being used by one of Pope's gang in "The Armory" (S1E02). It is possible that this is the civilian version of the Heckler & Koch G3, the HK91, as noted by the lack of the grenade launching lug on the barrel. It also appears to have a flashlight attached to side of the front sight block.
L1A1 SLR
The British variant of the FN FAL rifle, the L1A1 SLR is seen in the hands of of a resistance fighter inside a grocery store. What appear to be L1A1 rifles fitted with tri-rail and various other accessories are wielded by resistance fighters in "Eight Hours" (S1E10).
Springfield Armory M1A
One of Terry Clayton's men in "Sanctuary (Part 2)" carries a Springfield Armory M1A that John Pope later takes and uses in a shootout with Clayton's men.
Ruger Mini-14
In "Eight Hours" (S1E10), a resistance fighter at the school is seen with a Ruger Mini-14.
Rifles
M1 Garand
An M1 Garand can be seen on the right of this promotional image with the butt rested on the ground.
Winchester 1892
A Winchester Model 1892, or a clone of such can be seen in the hands of one of the resistance fighters, notably seen to open fire on an escaping Rich in (S1E10). Tom is later seen giving the rifle to Maggie.
In "What Hides Beneath" (S1E08), Sonya (Blair Brown), a woman that Tom, Hal, and Weaver encounter in Boston, fires on the group with a M48 Yugoslavian Mauser, an interesting choice for a survivor of the attack. These rifles were produced in post-WW2 Yugoslavia, and many have been imported into the United States. The Mauser is also seen in the hands of a member of the 2nd Mass in "Eight Hours" (S1E10).
Karen (Jessy Schram) uses a UMP9, as noted by the curved magazine, as her preferred weapon.
Heckler & Koch MP5A3
Dai (Peter Shinkoda) uses a Heckler & Koch MP5A3 fitted with a RIS handguard with attached flashlight and vertical grip as his preferred weapon. The MP5A3 is is carried by some of the "harnessed" teens in "Grace" (S1E04).
In "Sanctuary, Part 1" (S1E06), Maggie gives a Beretta 92FS Inox to Anne Glass (Moon Bloodgood) after an incident in the clinic.
Colt Gold Trophy M1911A1
A variant of the Colt M1911A1 is carried by Maggie (Sarah Carter). The pistol is fitted with adjustable sights and ivory grips and is first seen in "The Armory" (S1E02). She carries dual pistols in a black leather shoulder rig.
Colt M1911A1 (Nickel)
Maggie (Sarah Carter) also carries a different nickel M1911A1 along with the Gold Cup.
Colt M1911A1
In "Sanctuary, Part 1" (S1E06), a civilian survivor uses an M1911A1 to threaten Anne (Moon Bloodgood).
Colt Government
A wounded member of Pope's gang gives his Colt Government pistol in "The Armory" (S1E02).
Colt Single Action Army
John Pope (Colin Cunningham) is seen carrying a Colt Single Action Army as his sidearm, notably in "The Armory" (S1E02). In "What Hides Beneath" (S1E08), he uses his SAA to test out a new armor-piercing round.
Glock 19
In "Sanctuary, Part 2" (S1E06), Jimmy is seen pulling a Glock 19 during a confrontation with a Skitter in the school.
At the beginning of the premiere episode "Live and Learn" (S1E01), a Winchester Model 1200 Defender shotgun is seen used by a resistance fighter at a human checkpoint.
Mossberg 590a1 Special Purpose
In "Sanctuary, Part 2" (S1E06), a Mossberg 590 is used by Weaver to dispatch a skitter on route to kill Jimmy. The 8-shot is parkerized with ghost-ring sites and a speedfeed stock.
Winchester 1200 Ranger
Another resistance fighter is armed with what appears to be a Winchester Model 1200 shotgun.
Machine Guns
Browning M2HB
A Browning M2HB is the main heavy weapon used by the 2nd Massachusetts in Season 1. The machine gun is mounted in a Pontiac GTO.
FN M240B
The M240B is another weapon used by the 2nd Massachusetts. It's first seen being carried by Anthony (Mpho Koaho) in the series premiere "Live and Learn" (S1E01). Tom Mason (Noah Wyle) can be seen firing an M240B when his squad ambushes Pope's bandits in "The Armory" (S1E02). The Falling Skies website mistakenly refers to this machine gun as a .50 Caliber weapon, when, in fact, it uses the 7.62x51mm NATO round.
PKM
A PKM machine gun is seen being fired by Hal Mason (Drew Roy) when the squad ambushes Pope's gang at the end of "The Armory" (S1E02).
RPK
An RPK machine gun is seen being fired by Anthony (Mpho Koaho) when the squad ambushes Pope's gang at the end of "The Armory" (S1E02).
In Season 1's finale "Eight Hours" (S1E10), Tom Mason (Noah Wyle) can be seen firing an RPG-7 fitted with a special warhead manufactured from the aliens' "Mech" metal. The Falling Skies website erroneously refers to it as a "Bazooka" (which is a completely different weapon system).
Other Weapons
Molotov Cocktail
Tom Mason (Noah Wyle) fashions a molotov cocktail to distract several gun-wielding "harness" kids, when surrounded in the motorcycle store.