The mid-2014 war in Gaza gave Israel the opportunity to aww how many new weapons performed under combat conditions. This included ammunition. Israel introduced its 120mm APAM-MP-T (M329) multi-mission tank shell in 2011 but was not able to test it in heavy combat until the mid-2014 50 Day War with Hamas. The M329 is an anti-personnel and anti-materiel (vehicles or structures) round that has a programmable fuze that allows for air bursts and detonation when close to a moving target (like helicopters). The M329 acts like a high explosive round when fired at buildings or bunkers. The tank gunner can select how the fuze will operate before firing a shell. Thus the M329 fuze can be set to penetrate a wall and then explode inside, or detonate in the air over troops in trenches. This makes the M329 useful for destroying buildings or just killing or wounding enemy troops. Max range of the M329 is 5,000 meters and it is very accurate.
Israel developed the M329 because similar American multi-mission 120mm rounds had appeared earlier and Israel has used some of them in combat. Suggestions from Israeli troops led Israel to design their own multi-mission ammo like the M329. Multi-mission tank rounds began appearing in the 1990s and since then there have been several generations of such tank gun ammunition. Some of these American rounds proved very useful in Iraq and Israel a decade ago. These new shells were better at killing infantry, and destroying bunkers and buildings, rather than destroying tanks. With the end of the Cold War, there has not been a lot of tank-versus-tank combat, and existing anti-tank shells were more than adequate for that. But for post-Cold War combat new and improved shells would be useful.
Not surprisingly in the 1990s new shells were developed for these new conditions. In some cases older shells were recycled with new features. Thus 19,000 American M830A1 multipurpose 120mm tank gun rounds were modified to become M908 shells. This made them more lethal against bunkers, buildings and unarmored vehicles. In addition, there was the M1028, which is a 120mm shotgun shell (containing 1100 10mm tungsten balls, that can kill or wound at up to 700 meters from the tank), that began production in 2002. This shell, and the M908, were what American M-1 tanks use nearly all the time in Iraq.
Israel had pioneered both types of “irregular combat” tank ammunition and used their versions heavily in Palestinian areas after Israeli troops withdrew from Gaza and that are became a Islamic terrorists sanctuary. The M908 and M1028 shells make tanks much more useful in urban fighting. Hostile gunmen often take cover in buildings, or trees and crops. The M908 can knock down buildings, and the M1028 can clear out anyone sniping at you from lighter structures or vegetation. The M329 provides even more flexibility for when tanks are not fighting other tanks and replaces the capabilities of both the M908 and M1028. Now, like those two older designs, the M329 has plenty of combat experience to demonstrate what worked and how well.