Muzzle brake inside dimensions

[spfld]

Is there a rule of thumb for how much larger the bore of a brake needs to be over the diameter of a bullet?

 

[mike in co]

yes and most brake manufacuters will provide it with thier product......
generally i see .010 to .020 total not per side...this means the brake must be on straight...

mike in co

Is there a rule of thumb for how much larger the bore of a brake needs to be over the diameter of a bullet?

 

[alinwa]

.020 over bullet diameter