Resident Evil 5

H&K USP

Chris uses a HK USP in the teaser trailer. It's been confirmed this weapon is in the final game but is labeled H&K P8. It appears to be fitted with a custom compensator.

Chris with his custom H&K USP at the ready.

Beretta 92FS

The Beretta 92FS's are Chris's and Sheva's handguns.

Chris with a Beretta 92FS.

Sheva with her Beretta 92FS with an accessory rail mounted laser.

Chris with his Beretta 92FS

Sheva reloads her 92FS.

Beretta M93R

This weapon hasn't been seen in any pictures or trailers but has been confirmed by the Resident Evil Wiki. [1]

Beretta PX4

Like the M93R, this weapon hasn't been seen but has been confirmed.

Samurai Edge

Possibly a secret weapon.

S&W M29

A confirmed magnum.

Desert Eagle

Another magnum, caliber unknown.

S&W M500

Another confirmed magnum.

Ithaca 37 shotgun

Chris has been shown with this weapon. It has an Ithaca magazine tube cap but features a Mossberg 500 tang safety, making it a video game combo gun.

The second picture seems to indicate that this is an Ithaca 37- the "tang safety" looks like a sling attachment point from that angle.

Yes, it most certainly is. I downloaded the demo for this game on my PS3 and since you fire from an over the shoulder view, it is clearly visible as a sling swivel. If you check your inventory ingame, it even calls it an Ithaca M37 shotgun.

File:RE5-6.jpg

Chris fires a fictional shotgun while Sheva fires her 92FS.

Sako M75

A screenshot featured in a magazine shows Sheva holding this rifle, .233 calibre.

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Sheva with a Remington 700 rifle.

Benelli M3 Super 90

A picture on Wikipedia depicts Sheva posing with an M3 Super 90 shotgun.

Sheva armed with a Benelli M3 shotgun.

Striker

A confirmed shotgun.

Sawed off shotgun "Mad Max" Style

A possible secret weapon.

Scorpion SA Vz. 61

Sheva is shown with this weapon strapped to her back while fighting off enemies. Caliber is unknown, more than likley .32 ACP. Chris can later get one in the game. Also Chris is shown with it in recent gameplay on the barge

HK MP5

On the cover of a magazine, Sheva is seen with an HK MP5 with a telescopic stock and a Surefire tactical flashlight. It also has a red dot sight o the top which is hard to see. This weapon has been confirmed by Gamepro magazine as a usable weapon, Chris is seen using this weapon ingame.

AK

In one of the gameplay trailers it looked like a variant of an AK 74 or something similiar

File:RE5AK.jpg

SIG 556

More than likely, this is the weapon we have seen in the trailers where Chris is firing what might have been an M16. However, this weapon is a semi-automatic only.

[2]

M16?

In one of the trailers you seem to be firing what looks like an M16 or an M4. The automatic used in the trailers looks smaller than the Colts..

Dragunov

This weapon can be seen in the mutated bat fight if you look very closely at Chris's back.

H&K PSG-1

A confirmed sniper rifle.

Unknown Grenade Launcher

A grenade launcher has been confirmed but not what kind. Probably an M79.

Grenades

Flash, Explosive, Flame grenades have been confirmed.

PKM???

In several magazines, Chris is shown firing what appears to be a Kalashnikov PKM mounted turret style on a military Hummer.

Browning M2

In a recent trailer Sheva is seen using a truck mounted Browning against motorcycle riders and other trucks.

GAU-17

In the same trailer as above Chris is seen using a GAU-17 mingun against enemies in what looks like an oil drilling platform. Sheva is shown firing this weapon mounted on a tripod on the trunk section of a military Hummer.

RPG-7V

A terrorist is seen using one to shoot down a helicopter in the trailer. It is also used by a BSAA grunt in a helicopter.

Mercworx Goliath

Chris Redfield uses a Mercworx Goliath as his combat knife. This knife is easily recognizable by it's length and the unique "chili" handle exclusive to the mercworx line of knives.

Rocket Launcher

Two possibly secret rocket launchers have been confirmed.

Noctovision Rocket Launcher

Infinity Rocket Launcher