My question is about the “crown” on a muzzle break.
I understand the importance of the crown on a rifle barrel muzzle.

However, if the barrel has a muzzle break, is the crown on that muzzle break important?

For example, if the crown on the rifle barrel is in perfect condition, but the crown on the muzzle break is lightly damaged, will that damage affect accuracy?

Thanks in advance for your help.

Yes it will. Depending on the brake, a damaged crown on the brake can actually hurt accuracy more than the same damage on the barrel crown.

Good shootin' -Al

I would like to see the damage. I would think, as long as the damage does not cause contact with the bullet, it shouldn't have much effect.
Al, have you tested this or can you reference reliable tests? I don't really want to put a brake on one of my barrels to test this but I suppose I can, if necessary. GD

How can it effect it if the ID of the brake is greater than the bullet diameter by several thousandths

In both cases that I have first hand experience with, the damaged brake 'crown' showed significant accuracy losses. They were tested A-B-A to verify the results. Both were caliber specific...not 'universal' brakes.

The first one was a 257 WBy with a KDF brake and the second was a 300WSM with a Vais brake. In both cases, fixing the damaged brakes corrected the accuracy issues.

I don't doubt that depending on the individual brake, you may or may not see accuracy issues with a damaged brake 'crown'.

Fortunately, it's easy to test.

Good shootin' -Al

Thanks Al, Not having tested it, I couldn't say for sure. I've got a couple of seconds here that I could experiment with. I just have to decide what barrel I want to put a brake on. I've made and installed a couple hundred for others but have never had one on one of my own rifles. GD

I'd sure be interested in your findings. Like you, I don't have any on my personal stuff. I've been pondering a 375 Ruger so that might change my mind!

Good shootin' -Al

Gas surrounding the bullet when it leaves the crown will divert differently if the crown on the muzzle brake is not even.

Isn't the bullet already gone by then? Seems like the same thing could happen if all the holes in the brake are not perfectly symmetrical, Not arguing, more curious

the hitch is the burning powder hits the air and causes another pressure wave at the end of the barrel while the bullet is still passing through that shockwave…. So that end of the muzzle explosion pressure wave can impact trajectory. A good deal of that occurs after the bullet leaves the area, but a bunch of it occurs while she’s still in the zone.

Gas is blowing past the bullet at the muzzle, yeah I have thought about the holes . There are brakes with the bottom of the break undrilled . I have one muzzle brake(which I hate) and its holes are drilled right but the internal finish is horrendous.

The gas goes faster than the bullet as soon as it leaves the barrel - still at a high pressure but no longer contained by the bullet. A damaged crown will cause uneven gas flow around the base of the bullet that will upset the alignment of it. The spin might fix it but it's not a good start.