GrovTec G-Nite Flash Suppressor Black Nitride

A: yes it will fit and work just fine as long as the thread size on the barrel is correct 5/8-24 tpi

A: Kenneth, yes Sir it is a 30 Cal Brake and will work on a 5/8x24 thread pitch or with a 1/2 x 28 to 5/8 x 24 Barrel Thread Adapter --- https://www.downrangeproductsco.com/product/12-x-28-to-58-x-24-barrel-thread-adapter-stainless/

A: Yes, as long as you have a barrel with 5/8×24 thread pitch. Hope this helps.

A: Yes both the .300 BLK and the .308 Win use a .308 caliber bullet, this will work on either as long as you thread pitch matches, if not there are adapters like this one https://hughesprecision.com/product/12-28-id-to-58-24-od-barrel-adapter-thread-converter/