The bubble is used to properly install the BERGARA BA0006 ST1 MUZZLE BRAKE 30CAL. You will want to make sure the rifle is level then when installing the muzzle brake you will torque it down and check to ensure the muzzle brake is also level ensuring it is aligned properly.
The Bergara HMR Pro in .308 uses 5/8x24 threads and should be compatible with this muzzle device. Email us at Techsales@opticsplanet.com for assistance.
Yes. Your Savage rifle uses 5/8x24 threads and fires a bullet with a diameter of 0.284", which is compatible with this .30 cal muzzle device.
Any 30/308 caliber muzzle device threaded 5/8x24 will fit and function with your rifle. I would recommend reading the How-To Guide linked below to help you select a muzzle device that fits your intended purpose.
https://www.opticsplanet.com/howto/how-to-select-a-muzzle-device.html
Its the same 35% recoil reduction.
Yes it can.
Yes it can.
No it will not.
Yes it will.
Yes 300 is smaller than 308