M16 rifle grenade

Right when the M16 was adopted the US realized the rifle grenade’s days were numbered. While there are anti-personnel rifle grenades, the primary purpose for rifle grenades was the anti-tank role. By 1960 tank armor was so thick a US rifle grenade just couldn’t penetrate the armor. So what do you do?

Well the Swiss doubled down and made 1kg rifle grenades, but they were the only country that had a rifle that could launch such a large rifle grenade. The US saw the rifle grenade was going to be a losing game, so they started developing the LAW. The Russians were well ahead of the curve, they saw the RPG was the future very early on…of course, they have much more experience with infantry fighting tanks.

Much of NATO tried to extend the life of rifle grenades by making them very big, but then adding rocket assist. Problem is, the rocket doesn’t help the rifle grenade clear the rifle, so those heavier grenades were still completely abusive to the rifles. The French are still using rifle grenades, but not in an anti-tank role.

The joint where the AR receivers come together is a very questionable area for rifle grenades. But you have upper & lower aluminum receivers joined by a steel cross pin. The pin area elongated, and then eventually the section of the upper that went down into the lower would break off.