XM8 is G36, which improves the technology, materials and vest. If you think G36 is not good, XM8 is not good. Until the end, it is impossible for XM8 to be assembled on XM25 or the expected semi-automatic Grenade launcher module. This requirement is too high. This is why XM8 and XM25 are increment 1 and increment 2, respectively, and the combination is increment 3. If you really want to combine XM8 with Grenade launcher, you have to make a big change. Because the modernization of the army has changed from one-step dressing-up to the current spiral mode, OICW has been cut into three pieces. Since the increment 1 has been cut, the combination will be fine, and XM29 will naturally disappear.

At present, only XM25 is still alive and is being tested in actual combat. It seems that the basic requirements have been met. The core of XM29 is semi-automatic air-exploded Grenade launcher and sight with laser ranging, uncooled thermal camera and automatic trajectory calculation. Now all these have been realized on XM25, and the main purpose has been achieved. As for putting short-barreled rifles together, it is somewhat redundant. In the end, it turns out that the weight is unacceptable and there is great pressure to reduce the cost. Now it seems that XM25 needs nothing but waiting for the cost of various technologies to come down. Because of electronic technology, the cost of miniaturized fuze and fire control in the Big Bang was much lower than that in the 1990s.

Moreover, the XM29 sample gun that can be launched in the end is also an improved combination of G36 and 20mm semi-automatic Grenade launcher, which cannot be used alone. The combination of XM8 and XM25 has never been realized.