Murderers' Row is a 1966 spy comedy directed by Henry Levin. It's the second of four films about the adventures of "super spy" Matt Helm, preceded by The Silencers (1966) and followed by The Ambushers (1967) and The Wrecking Crew (1969). All films are very loosely based on the novels by Donald Hamilton; while the original novels are written in serious key, the films tend to be parodies on James Bond genre.
The following weapons were used in the film Murderers' Row:
Matt Helm's (Dean Martin) main weapon and a valuable plot item is a "ten-second delay gun" that appears to be a Hy Hunter Bolomauser, a pistol version of Armalite AR-7 that was manufactured in 1960s. The pistol several times passes from Matt to other characters and back again.
A unique version of MBA Gyrojet, six-barreled pepperbox-style pistol is used by Julian Wall (Karl Malden) during the chase on hovercrafts. In Wikipeia article this pistol is called 12-barreled but the screenshot shows a different picture.
In one scene Coco Duquette (Camilla Sparv) is seen with a "Freezer Pistol" that produces a spray, capable to turn a man in a snowman. Later this pistol is used by Matt Helm (Dean Martin). The gun resembles a Baby Browning though it can be simply a water pistol.
The guards in Wall's headquarters carry M1 Carbines, fitted with heat shields, pistol grips, underfolding stocks and M9 flash hiders. In one scene Matt Helm (Dean Martin) fires a captured carbine that produces the sound of full-auto fire (like M2 Carbine) but the holes from the bullets appear with the speed of semi-auto shooting.
In one scene Julian Wall's (Karl Malden) is seen. It contains six bolt action rifles with sniper scopes (supposedly Winchester 70s), two M1 Carbines with folding stocks, three revolvers (unidentified), a pistol (unidentified), Webley No. 1 Mark 1 flare gun and MBA Gyrojet pistol. Except Gyrojet, other guns aren't used in action.