Okay, this might not actually be recent but I just found out about it from re-watching a Bones episode last night. I don't really like guns but I have to admit the bullet sounded awesome.
The bullets are actually separate slugs that are fit into the same cartridge, but the bullets are joined together by a tether which prevents them from getting too far away. The bullets are designed this way in order to increase the chances of getting a shot.
At least, it seemed awesome at first. It was supposed to be designed to make for any deficiencies on the part of the marksman and increase the chances of the bullet hitting the target but the build and design of the bullets actually cause a lot of problems.
The tether causes the bullets to experience an aerodynamic drag and this makes the MI bullets less stable than normal bullets. The bullets also affect one another, so if anything should happen to one of the bullets, it would affect all the bullets. The bullets have a very short range at which they can effectively be used. The bullets also have a very low penetrating power. It is also really expensive, especially for what results you can expect from the bullet.
The bullets that seemed like a marvel of technology at first ended up turning out to be wack. I guess this is why the bullet is not all that popular.
