The Update 21 Experimental Branch is now available for Hell Let Loose on Steam, giving players an early look at five weapons, rifle grenades, selectable fire modes, Conquest and armor adjustments. This is a test build rather than the public release, which makes the distinction important for anyone running version-dependent third-party software.
Rifle grenades are the headline addition
U21 introduces launcher-equipped rifles that can alternate between standard ammunition and several grenade types. Holding the fire-select control opens a radial menu, while tapping it swaps to the most recently chosen grenade. The transition is not instant, and its timing changes depending on whether the weapon has already been fired.
The available ammunition covers three jobs:
- fragmentation grenades with an explosion radius similar to that of a regular hand-thrown grenade;
- smoke rounds for concealment;
- anti-tank grenades with limited armor penetration.
AT rifle grenades can attack lighter tanks from behind, damage the tracks of medium and heavy tanks, and destroy structures other than garrisons. Every rifle grenade uses impact detonation for gameplay purposes.
The five test weapons are the US M1903A3 Springfield and M7 launcher for the M1 Garand, the Soviet ROKS 2 flamethrower, Germany’s Schiessbecher for the Karabiner 98k, and the No.1 MK I Cup Discharger fitted to the British and Canadian SMLE. They are temporarily unlocked for everyone on the Experimental Branch but will require the appropriate loadout levels at release.
Fire selection changes weapon behavior
Historically selectable firing modes have been enabled on the MG34, FG42, STG 44, BAR, Thompson M1, Thompson M1928a1, Bren Gun, Sten MK2 variants, Sten Mk5 and PPSH 41. PC players currently toggle them with Caps Lock. The BAR also offers fast and slow automatic settings.
This is more than a control option: one weapon can now produce different firing patterns without changing the loadout. Recoil profiles or trigger automation configured around a single cadence may therefore behave inconsistently until they account for the active mode.
New rifle-grenade kits are assigned to the Rifleman, Medic and Engineer. Their ammunition differs by role, with the Engineer receiving three AT, two fragmentation and one smoke grenade. Other revisions include a US Marksman loadout with the Springfield and an explosive ammo box, an M3 Grease Gun for the default US Tank Commander, an M1 Carbine for the standard US Anti-Tank role, blowtorches for default Crewmen and node construction with the Technician wrench.
Test-branch conditions and armor changes
Players can join through the Hell Let Loose beta settings in Steam by selecting Exp_Branch. Switching branches replaces the active game build, so software compatibility confirmed for the public client should not be assumed to carry over.
Self-propelled artillery receives another zoom level for its gunner position. The default SPA located at each team’s HQ is currently set to respawn automatically seven minutes and thirty seconds after being destroyed on the Experimental Branch.
What this means for players using software
Treat the Experimental Branch as a separate compatibility target. New weapon records, ammunition types, loadouts and client-side code changes can affect overlays, inventory parsing, aim logic or other modules even when the game starts normally.
- Do not attach a public-build tool to
Exp_Branchunless its provider explicitly lists test-branch support. - Check the software update status page again after moving between the experimental and public clients.
- Keep separate recoil configurations for weapons whose cadence can now be switched.
- Expect new launchers or grenade types to be missing or misclassified in ESP until their identifiers are supported.
The announcement does not mention an anti-cheat change. There is therefore no factual basis to claim that U21 requires a new HWID spoofer or an anti-cheat-specific waiting period. Before launching a session, compare the supported client version shown in the Hell Let Loose software catalog with the Steam branch currently installed.
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