Star Trek IV: The Voyage Home

The following weapons appear in the film

M1911A1

The M1911A1 pistol appears in the hands of U.S. Marines onboard the U.S.S. Enterprise aircraft carrier in the 20th century in the scene where Pavel Chekov (Walter Koenig) is captured, and again when he falls and injures himself trying to escape.

M1911A1 .45 ACP

M16A1 Rifle

The majority of the U.S. Marines aboard the U.S.S. Enterprise aircraft carrier can be seen armed with M16A1 rifles as their primary weapons in the scenes where Chekov is captured and later during his ill-fated escape attempt.

M16A1 with 30-round magazine 5.56x45mm

Chekov is captured by Marines armed with M16A1 rifles

U.S. Marines chase after Chekov with M16A1 rifles

Unknown Smith & Wesson Revolver

In the scene where the protagonists rescue Chekov from Mercy Hospital in San Francisco, San Francisco P.D. officers are seen brandishing Smith & Wesson revolvers of unknown make and model while persuing the protagonists, who use the ship's transporter to escape.

M203 Grenade Lancher

In the scene where Chekov attempts to escape from the Enterprise aircraft carrier, one of the Marines chasing him can be seen armed with an M203 grenade launcher attached to his M16A1.

M16A1 5.56mm with M203 grenade launcher 40mm

A Marine in the background can be seen with an M203 grenade launcher mounted on his M16A1

Unknown shotgun

Seen in the hands of Marines on the Enterprise of 20th Century, oddly we see an equal amount of these along with the M16s