The Guns of Navarone and The Dirty Dozen seemed to be the main influences here...

I thinking of the adult and cynical tone of The Dirty Dozen and the philosophizing over the costs and morality of war in The Guns of Navarone. Plot-wise there are similarities as well. A rag-tag band of renegades (including ex-con Jyn Erso) goes on a suicide mission to take out a super gun emplacement.