Squaring and crowning muzzle

[gunsandgunsmithing]

I can't think of many things less critical to accuracy than the difference beteen a flat, recessed or a 11° crown. Bedding, chambers, gun balance, TUNE...Yeah, those things actually matter. But I've seen every crown win. That's all.

 

[WSnyder]

I've read some discussions on indicating the muzzle where
there were some who recommended indicating the grooves and some
who preferred the land tops.

I have a gut feeling---at least for cut rifling---to use the land tops because
that is the primary reamed hole.

How about other, more knowledgeable, opinions ? Does it even matter ?

A. Weldy

I indicate off of the original hole diameter for cut or button but am looking forward to and answer from the professionals.

The question is do you have a barrel where all the lands and grooves are perfect and equal? If so then it probably doesn't matter. What if on a cut barrel one groove had an extra pass and it's deeper? What to do if two had an extra pass? What if a button barrel has a funky groove or land? Considering barrels tend to be around a 70% groove to 30% land ratio which will the bullet be influenced the most by? The deal is you'll have to see what you have in hand before you can figure out what you might want to do about it and they aren't all the same all of the time.

 

[spitfire_er]

I do a lot of threading for suppressors on hunting rifles, varmint, and PRS type rifles. I'm only really worried about the last 3/4-1" of bore before the crown on most calibers. Crown style isn't as critical IMO as long as it's concentric.

 

[urbanrifleman]

I can't think of many things less critical to accuracy than the difference beteen a flat, recessed or a 11° crown. Bedding, chambers, gun balance, TUNE...Yeah, those things actually matter. But I've seen every crown win. That's all.

#1. Shooter.

 

[DonkeyHote]

I personally like straight crowns recessed a bit to protect the barrel.
The gunsmith did my two barrel with strait crown uses nothing else. KW precision.

I'm a toolmaker by trade if that means anything.

 

[LVLAaron]

That's what I do. Straight, but I recess it a bit.

 

[butchlambert]

I personally like straight crowns recessed a bit to protect the barrel.
The gunsmith did my two barrel with strait crown uses nothing else. KW precision.

I'm a toolmaker by trade if that means anything.

I'm confused? What does a toolmaker have to do with cutting crowns?