The following weapons were used in the television series Sliders:
An Astra 400 was used in Season 3's "Dead Man Sliding" (S3E10) as a futuristic looking tranquilizer gun by Contestant Coordinator Taryn Miller (Perrey Reeves). A laser was clamped onto the locked-back slide to make it appear futuristic.
The Glock 17 was first used in the Pilot episode when Quinn Mallory (Jerry O'Connell) was given one of these pistols by a resistance fighter on the world where America was occupied by the Soviet Union. These pistols subsequently appeared in quite a few other episodes.
The Timecop Beretta (Dressed up Taurus PT99AF)
In Season 2's "El Sid" (S2E05), the handgun carried by Sid (Jeffrey Dean Morgan) appears to be the weapon that's known as the Timecop Beretta. This visually modified version of the Taurus PT99AF was used not only in the film Timecop, but also in the series Stargate SG-1 and Stargate: Atlantis.
Norinco Type 56
The USSR soldiers in "Pilot" (S1E01) were armed mostly with Norinco Type 56 copies of the AK-47 assault rifle. These rifles were also seen in many other episodes. In "Slither" (S3E22), both Quinn Mallory and Rembrandt Brown (Cleavant Derricks) used Type 56 rifles after taking them from tobacco farmers (on a world where tobacco was illegal).
Norinco Type 84
The USSR soldiers in "Pilot" (S1E01) were also armed with many Norinco Type 84S assault rifles, including at least one Type 84S Target with a long RPK-style barrel.
In the Pilot, anti-Soviet resistance fighters were armed mostly with M16A1 assault rifles. Hilariously, the resistance fighters' T-shirts showed the Statue of Liberty holding an M16A1 above her head (in defiance of similar Marxist-Leninist-themed T-shirts and flags). M16A1s were also used in many episodes by military personnel, usually with M16A2-style hand guards, including Colonel Rickman's (Roger Daltrey) soldiers in the two part episode "The Exodus" when they massacred civilians outside of Rickman's base.
A few M16A2 assault rifles were also used by Colonel Rickman's men. Quinn Mallory was seen using an M16A2 in the episode "Dinoslide" (although it looks as though his gun lacked the fencing around the magazine release, which means that it was probably an A2 upper on an M16 SP1 lower receiver). A resistance fighter fires one on a Cromag soldier in the season 4 ep "The Dying Fields" Some of the M16s featured in seasons 4 and 5 have M16A1 barrels and flash hiders.
Heckler & Koch MP5A3
The Heckler & Koch MP5A3 submachine gun first appeared in "Fever" (S1E03), seen used by the California Health Department soldiers.
DefTech 37mm launcher
In the episode "In Dino Veritas" (S2E11), a dinosaur poacher used a DefTech 37mm launcher to shoot in vain at the Allosaurus.