Sons of Anarchy

M4A1 Carbine

The plot of the first episode revolves around a cache of M4s stolen from the Sons by the Mayans (a rival biker gang). Clay (Ron Perlman) uses one at the end of the episode after taking it back from the Mayans.

Glock 17

This is also involved in the plot of the first episode, as the Mayans also stole Glocks from their warehouse (Note: Both the M4s and the Glocks were destined for the "Niners", a gang that also makes appearances in "The Shield"). Several of the bikers, including Jax (Charlie Hunnam) also use them at the end of the episode when they steal the guns back from the Mayans. (When Jax's Glock is seen lying unloaded on his coffee table, it clearly says 9x19mm on the slide if you watch the episode on a big-screen HDTV, so it's definitely a Glock 17.)

Heckler & Koch USP Expert

Clay (Ron Perlman) carries a Heckler & Koch USP Expert (recognizable by its slightly longer barrel and slide) during the confrontation at the end of the first episode. It is possible that this gun will re-appear in future episodes.

Unknown short-barrel .357 revolver

This revolver (with some NICE grips) is given by Ron Perlman as a gift to the Nords (after Jax beat up one of their members for dealing drugs to his pregnant ex-girlfriend.) It is a .357, as can be heard from Clay (Ron Perlman) in the conversation.

Unknown revolver

Jax can be seen taking a steel revolver with rubber grips from a drawer in his ex-girlfriend's (actually his) house (conveniently located next to some baggies of methamphetamine). He is seen strapping this into an ankle holster before the raid on the Mayans' warehouse.

It looked like it might have been a Smith & Wesson Model 60.

Couldn't tell. I have an "old school" (Cathode Ray Tube) TV.

AK-47

Chibs (Tommy Flanagan) and his IRA contact bring disassembled AK-47s packed in oil drums to the Garage in the beginning of the third episode.

MAC-10

A burned MAC-10 can be seen among the remains of the arms warehouse when Hale arrives.

Ruger AC556

A Ruger AC556 with a short barrel can be seen being loaded by Clay at the Clubhouse in "Hell Followed".

Smith and Wesson M5946

Most commonly seen being used by Bobby

Jericho 941

In one episode a mayan is seen using one.