Archery expert Grizzly Jim reveals what Rambo's grenade arrow actually was. The film series, which began in 1982 with the adaptation of David Morrell's First Blood, follows Sylvester Stallone's John J. Rambo, a Vietnam War veteran who uses his unique skill set to combat dangerous enemies. Although the franchise generated mixed reception over the years, its action has been a source of consistent praise, and the exploding arrows were featured in multiple installments.

https://screenrant.com/rambo-movie-grenade-arrow-archery-expert-reveal/