This is part 2 of the 'Metal Gear Solid 4 weapons' guide. I will be highlighting a few of the best heavy weapons from Metal Gear Solid 4, and giving a brief description.

Rifles:

M4 Custom
It is basically a shortened model of the M16, and is the mainstay of U.S. Special Forces. It includes a highly-revolutionary 'rail system', which makes it compatible with a lots o add-on parts, almost like a 'Do It Yourself' gun. This is probably the gun I used most during my first play-through, as it can be heavily customised, it is useful in nearly every situation. For example, you can fit on it a silencer, a scope, a laser sight, a grenade launcher, a shotgun, two different grips to improve accuracy, and a flashlight.

The DSR-1
No we're really talking. The DSR-1 is a no-nonsense, bolt-action sniper rifle. Billed by its manufacturer as "the most sophisticated and technologically advanced tactical precision rifle in the world", it certainly packs a punch. Its integrated bi-pod means it's always ready to go, and despite its extreme loudness, it is always guaranteed to take down your victim, should you land a direct hit.

Mosin-Nagant
If you want something a little less brash and subtle, then the Mosin-Nagant is for you. Brandished by 'The End' in MGS3, the Mosin-Nagant is a special sniper rifle, as it uses non-lethal, tranquilizer ammo. While this gun is extremely noisy, if it's used from a distance (which is what it's designed for), you won't have a problem. This is one of the Metal Gear Solid 4 weapons that is essential when trying to complete the game without killing anyone.

Other/Special:

Rail Gun
The rail gun is acquired after defeating Crying Wolf in act 4 of the game. Of all of the Metal Gear Solid 4 weapons, it might just be the most powerful, when fully charged, and is said to pack the same power as a tank turret! There are no modifications that can be made to this weapon, but realistically, there are none that are needed.