The U.S. soldiers at Alcatraz island are seen swapping in their M16A2 rifles for plastic "Cure" rifles.
M240D Machine Gun
A U.S. soldier at Alcatraz is seen tending to an FN M240D machine gun, as noted by its barrel length and spade grips. For some reason, it is also fitted with the bipod of the infantry M240B/G models.
Browning M2
Another soldier is turning in a Browning M2HB to the armory.
Remington 870
Two of Magneto's brotherhood members are seen using Remington 870 shotguns when Wolverine (Hugh Jackman) enters the camp.
Mossberg 500 "Cruiser"
One of Magnerto's brotherhood members is seen using a pistol gripped Mossberg 500 "Cruiser" before being killed by Wolverine (Hugh Jackman).
"Cure" Pistol
After the armored van that transports Mystique (Rebecca Romijn), Multiple Man (Eric Dane), and Juggernaut (Vinnie Jones) is commandeered by the Brotherhood, one of van's guards uses a pistol that fires "Cure" darts to try and shoot Magneto (Ian McKellen) The pistol is fitted with a lime-green laser sight.
XM-92 Plastic "Cure" Rifle
The U.S. soldiers prepare against Magneto by swapping their metal weapons for plastic cure rifles instead. They are seen in the hands of the soldiers guarding the mutants accepting the "cure" and all the soldiers at Alcatraz are seen using these weapons. The designation is seen in two scenes (one of them deleted) showing the weapons in transport crates.
"Cure" Launcher
Some of the U.S. soldiers defending against the Brotherhood on Alcatraz island use shoulder fired launchers that launch exploding projectiles, releasing cure darts in volleys.
"Cure" Cannon
U.S. soldiers on Alcatraz use a three barreled cannon to fire large "Cure"-releasing disks at Magneto and his troops on the Golden Gate bridge, but he lifts up parts of the bridge to deflect the darts.
Trivia
Although in the film, All the US soldiers are asked to turn in all metal, guns and dogtags. But interestingly enough, they still have metal in their helmets and boots e.g. the boots' eyelets and shanks.