This guide will let you know where to find the Rope Gun in Sons Of The Forest. Go through the guide and follow the simple steps to do so.
You will need to make your way to the cave and break the barriers. Keep in mind that it is a very long cave so you must have some armor and grenades. Once you reach the large cavern, there will be a path in the back corner.
You will find a giant monster stuck, just use the explosives to blow them up and then go through. There will be a few different paths that you can take, but you have to follow the path all the way to the end to find the rope launcher. You can use it to get to different places.