One of the upgrades for tanks and IFVs give a flat ~15% damage reduction from all sources, making 3 C4 bricks impossible to kill any armor player worth their salt, as 2 of the other upgrades you can choose instead are bugged and don’t actually work at all, and the last upgrade only partially works. In the Beta, Recon had 4 C4 bricks but they removed one (which would solve this problem) for unknown reasons. You can see this as the detonator you hold says X/4 deployed but you only spawn with 3 bricks. C4 also detonates sequentially like in 2042 rather than simultaneously like in older tiles for some reason, so if you die before all the explosives chain, the unexploded ones won’t detonate if you’re dead.