Manufactured by Swiss Arms AG., the SGi-5k is the weapon of choice for veteran and expert Freedom, loner stalkers, and mercenary units in the zone. In all games, the SGI one of the most durable, powerful and accurate assault rifles in the game and a jack-of-all-trades type of assault rifle, although heavier than most of them. The weapon uses 5.56x45mm rounds.
The main drawback of SGi is that it can't mount a SUSAT scope, but in almost every other aspect it wins with other assault weapons - it is very accurate (as good as TRs-301 and GP37), it has shorter reload time than other NATO weapons and is one of most (if not the most) durable non-unique weapon in game - SGi is still enough accurate and doesn't jam as frequently as other rifles even if its condition goes past 70%. It can also mount a M203 grenade launcher, which makes it even better as a close-combat rifle. It is, however, pretty heavy weapon, weighing 4 kg empty.
The SGI 5k is commonly used by veteran-ranked members of the Freedom faction, and is also often used by expert-rank Freedom members as well. The SGi-5k is also used by several veteran and expert Mercenaries. Finally, several of the veteran-ranked soldiers of Monolith are armed with an SGI-5k during the final battle atop the Chernobyl NPP's superstructure.
It's purchasable from Skinflint after getting a friendly reputation with Freedom faction.
The player can also obtain an SGI in the Military Warehouses area from the veteran Freedom squad leader that will be ambushed by Skull's company upon entering the area Although the chances of finding it in good condition is somewhat rare.
There is a unique variant of the weapon: the Sniper SGi 5k which has an integral SUSAT-scope attached to it with an improved 4.0x zoom. You can find two of this variant on the guards at the entrance of the Freedom base in the Military Warehouses area. It can also still mount an underbarrel grenade launcher like the stock variant.
In game files there are leftovers of another version of SGi 5k, which supposed to have lowered weight (2.2 kg empty), but couldn't mount a grenade launcher.
The SGI must be upgraded to mount both an underbarrel grenade launcher and SUSAT Scope. It's upgrades are the same as all 5.56mm caliber assault rifles. It performs particularly well for any role it is upgraded to, however for no apparent reason player's turning speed is slightly, but noticeably reduced, making it quite hard to use, especially in heat firefight, but it works well as marksman weapon.
The SGi 5k is more available. It can only be purchased from Freedom after joining them.
A free SGi 5k upgraded to mount a SUSAT scope is given to the player for free upon joining Freedom.
There are a few SGI 5ks found in stashes in the Army Warehouses, one is in a stump where the coordinates are from an unknown stalker and Hog can also provide the location of one in the actual Military base for around 3000 rubles, which is located in the attic of a barracks structure.
In Call of Pripyat, the SGi is fully optimized as an assault weapon, it lost it's ability to mount a SUSAT scope and so isn't the best weapon for picking off distant targets but it can mount an M203 grenade launcher without any modifications. At stock configuration, the SGi has great damage, accuracy, average recoil and above-average durability. The weapon's performance at close range is exceptional, especially when fully modified for maximum firing rate and low recoil, however it is still hampered by the fact that it's a dedicated assault weapon, distant enemies are still a problem if one cannot use the iron sights properly.
A custom variant known as Strelok's SGI 5k can be found in the last stash of Strelok's Group in Yanov. This particular variant virtually eliminates the stock variant's shortcomings as it can mount all accessories without modifications and the increased damage, dealing more damage than any other NATO weapon in stock.
The weapon of choice of veteran Freedom members, as well as Mercenary units – nearly every squad of these factions will have at least one in the squad. Loners may carry this weapon, especially in the Yanov and Pripyat areas.
One can be found in a stash in the outer western area of the Jupiter factory's warehouses behind a red shack (you will get coordinates for it after helping Uncle Yar deal with mercenaries at Kopachi Village).