I want to make sure I have my threads right. In this one we can post untagged spoilers AND people get to bitch and moan about unrealistic depictions of weaponcraft in a show that features dragons, giants, undead, and people who can shapeshift or project themselves into wildlife?
The coconut opening trick I have seen is to pierce the eyes with a sharp object, drain the liquid through the holes, then strike the eye end of the coconut against the ground (or hit with a hammer). One of the eyes is usually softer than the other two, and if you can get through that one you don't need to open all three.
I've even seen people do this with a ballpoint pen. I use the corkscrew on a Swiss Army knife for this. None of the other tools on a typical SAK would...
Non-military, low-profile gas block guy speaking--I believe the milspec M4/M16 has a lug built in as part of the front sight base. During the AWB, civilian versions of the FSB were produced without it. There are replacement FSBs and clamp-on lugs that can be added to a lugless rifle, though.In a zombie apocalypse situation, duct tape and wire would probably suffice.