Muzzle crowns, muzzle brakes and accuracy

[ThatGuyHank]

So I'm playing around with an old rifle and I want to shorten up the barrel to make it more compact and "scout"-like. I know most consider an 11 degree crown to be the most accurate but I would also like to thread the gun for a muzzle brake considering the 7.62x54r is rather punishing even in longer barrel lengths. I want this "scout" to be as accurate as possible so I was wondering if an 11 degree crown is TRUTHFULLY the most accurate attainable crown. Also, how a muzzle brake will affect accuracy (if at all) and what type of crown is most advantageous for use on rifle with a muzzle brake.

Thanks for any insight you all can provide. Cheers.

 

[LoonWulf]

From my understanding of the subject, 99% of a crowns job is to keep the end of the bore from getting dinged. If the muzzel is perfectly square a crown isnt necessary with a muzzel brake? I cut the barrel on my nagant with a hack saw and stoned it as close to flat as i could get it, then used and old lee case trimmer and 300 pilot wraped in a single layer of teflon to get it a tad closer. Gun still shoots the same 1-1.5"s it did before i lopped the barrel off.

I also do know that alot of people have there own preference as to how a barrel is crowned.

 

[briansmithwins]

All I know about crowns is that they need to be consistent.

On my AK I tested the AK74 brake vs a muzzle nut and flash hider. There was no difference between the brake and nut, the flash hider group was ~1.5x the size of the other two.

BSW

 

[ThatGuyHank]

There was no difference between the brake and nut, the flash hider group was ~1.5x the size of the other two.

That's interesting, I don't have any firearms that are threaded currently so I couldn't conduct such a test. Do you have pics of the groupings?

From my understanding of the subject, 99% of a crowns job is to keep the end of the bore from getting dinged.

I've heard that as well. But I have also seen a lot of gunsmiths recommend or tout the 11 degree angle crown as the most accurate. Even though the muzzle brake is on the gun I still would think the crown would affect trajectory. I'm not sure which is why I asked

 

[LoonWulf]

Im sure if your crown/end of muzzel was not concentric it would cause accuracy issues with or without a brake.

 

[30Cal]

...I want this "scout" to be as accurate as possible so I was wondering if an 11 degree crown is TRUTHFULLY the most accurate attainable crown...

The effect of the crown type is going to be extreeeeeeeeemely subtle (i.e. not going to be measurable). As long as the job is done well, it doesn't matter, so my advice would be to go with whichever your gunsmith is most comfortable in doing.

Also, a lot of the surplus rifles in that caliber are not very good about putting the bore down the center of the barrel, so the 11degree crown might infact work out terribly whereas one that's cut with a mandrel would be more appropriate and give better results.