...when they were in the field Cain rose against Abel his brother and killed him.
Method not mentioned.
Nothing in accurate about it- the message is that it is NOT the weapon, it is the person behind the weapon that is thr source of evil. In David’s hands, the rock was used for good, ie, killing an enemy combatant to save the Israelites, while in the hands of Cain, the rock was used for evil, murdering his brother. It’s not the rock that is evil, it is the person who has evil In their hearts which is the problem. The evil person can choose whatever object they like to carry put their evil deeds, UT it doesn’t make the object itself evil
That was the message.
“Archaeologists Discover AR-15 Cain Used To Kill Abel”
https://babylonbee.com/news/archaeologists-discover-ar-15-cain-used-to-kill-abel/