-The extended cartridge is for such a high rate of fire the cartridge holding up to 150-175 shots. The rear grip itself is already small and held around 50-75 shots, thus why the extended cartridge was equipped to it.

-The suppressor's main job is not actually to silence the gun (although it does to an extent) its main job is actually to keep the weapon from overheating as quickly. Inside the tubing, there is a water-based coolant that keeps the gun from overheating as quickly. This is essential for urban warfare, breaching a large house with less of a risk of overheating means you will get more shots off before becoming venerable to counter fire