Muzzle brakes based on Fortis recoil compensators.
White and black variant, with and without side details.
You can purchase the whole pack here:
This started as an experiment with booleans, keeping Maya history nodes intact for quick cleanup of geometry and utilizing Zbrush dynamesh, effectively reducing time for the making by a large margin. In this way I was able to lower the whole mesh just by changing numbers on the history tab, making a very quick low poly version that needed a bit of cleaning, while keeping the higher poly copy of the mesh for Zbrush. A preview of this process is in the last pic.