Here is a fact about Valentines Day that few people know about.
On Valentines Day 1969 in South Vietnam, Chuck Mawhinney and his spotter were on patrol and spotted Viet Cong insurgents across a river. Knowing that there were multiple insurgents, he swapped his M40 sniper with his spotter's M14 rifle with an early infrared scope. The insurgents were seen trying to cross the river while holding their AK-47s over their heads. Knowing that they will get to US forces after crossing the river, Mawhinney had to take action.
By using his fast semi automatic M14, he fired 16 rounds and killed 16 Viet Cong insurgents (all headshots). He started to take heavy fire as he forgot the rule never firing his rifle twice or more in the same area. Mawhinney escaped and lived to tell the tale.