Games like Project Reality 2
Squad
Squad is a large scale combined arms multiplayer first-person shooter emphasizing combat realism through communication, team play, emphasizing strong squad cohesion mechanics as well as larger-scale coordination, tactics, and planning. It features 20 large open maps, vehicle-based combined arms gameplay, and player-constructed bases to create a heart-thumping, visceral gaming experience with split-second decision-making in real-world scale firefights.
Escape from Tarkov
Escape from Tarkov is a hardcore and realistic online first-person action RPG/Simulator with MMO features and story-driven walkthrough.
Insurgency
Take to the streets for intense close quarters combat, where a team's survival depends upon securing crucial strongholds and destroying enemy supply in this multiplayer and cooperative Source Engine-based experience. The follow-up game to the award-winning Source mod, Insurgency is highly competitive and unforgivingly lethal, striking a balance between one-life gameplay and prolonged action.
Arma 3
Arma 3 is a truly massive military simulation sandbox game. It offers a wide variety of true/sci-fi combat situations in both singleplayer and multiplayer modes. It also comes out of the box with a very powerful editor that allows players to create their own scenarios, campaigns and mapmodes both for single- and multiplayer use.
Battlefield 2
In Battlefield 2, players will choose to fight for one of three military superpowers: the United States, the Chinese, or the newly formed Middle East Coalition. Armed with the latest modern weaponry, players can take control of any of the game’s 30+ vehicles to engage in major conflicts with over 64 players in some of the largest online battles on the PC. Additionally, persistent character growth allows players to rise through the ranks and attain the ultimate rank of General.
Breach & Clear
Breach & Clear brings deep tactical strategy simulation to PC, Mac and Linux! Build your Special Operations team, plan and execute advanced missions, and own every angle. Choose your real-world squad -- US Army Rangers, Germany's KSK, Canada’s JTF2, UK SAS, and more -- and take on a variety of foes with different skill-sets and abilities. Learn to approach, engage, and dominate your opponents through superior tactics and training.
Rogue Warrior
Rogue Warrior is a character-driven, first-person-shooter, featuring Richard Demo Dick Marcinko's explosive personality in an action-packed single player campaign, and intense multiplayer combat.
Delta Force: Black Hawk Down
In late 1993, the United States launched dual military operations in Mogadishu Somalia. Delta Force Operatives and Army Rangers were sent in to capture Somali warlords and restore order. Experience the intense combat of Operation Restore Hope in this ground breaking first person shooter. As a Delta Force operative participate in a number of daring and intense raids against the oppressive Somali warlords in and around Mogadishu.
Tom Clancy's Ghost Recon
The Red Army is back. Now that Russia's government has collapsed, a hardline leader is bent on taking over the republics. Enter Ghost Recon, an advanced, futuristic squad of U.S. Army soldiers. Unlike previous Rainbow Six games, the setting is much more focused on the military instead of anti-terrorist maneuvers. Next-generation inventory and weapons will give players a glimpse into the real U.S. Army "Land Warrior" program on which Ghost Recon is based.
Global Operations
Global Operations is a first-person tactical shooter computer game developed by Barking Dog Studios and published by both Crave Entertainment and Electronic Arts. It was released in March 2002. (Wikipedia)