How to Crown a Barrel

[Highpower]

That's a great example Dave.

[Highpower]

(06-02-2014, 05:52 PM)EdK Wrote: What's the purpose of that end treatment?

Ed

It recesses the bore and the rifling deeper into the end of the barrel to protect them against damage from scrapes or bumps. Dents and dings toward the outside diameter won't hurt accuracy. Dents and dings on the inner diameter destroy accuracy. Kind of like bumpers on cars. In a low speed impact you might bend the bumper but at least you won't smash the radiator, and you can still drive it home.

In cases where there are muzzle attachments being used, like a compensator or flash suppressor etc., there is no need to recess the crown because the attachment encloses and protects the end of the barrel.

[unioncreek]

I used different types of crowns depending on what I'm using the rifle for. I use a recessed crown for my rifles that get beatup and bounced around in the truck and a 11 degree crown for target rifles. When you crown your barrel you need to make sure that there are no burs left on the bore. The way I check these is with a Q-Tip, if it hangs up on the edge or the bore I use 1000 grit wet/dry sandpaper on my finger to just lightly touch it up.

Bob

[Arbalest]

Has the barrel been shortened at the muzzle?

[doubleboost]

The barrel has been shortend and screw cut for a moderator
It is a .20 calibre FAC rated air rifle
Just looks like it has been faced off square
John

[Highpower]

Often times barrels with threaded muzzles use a flat 90° face but they come with a threaded protector cap. That way if you want to shoot the rifle without it's normal muzzle attachment, you just screw on the protector cap to protect the barrel threads and the crown.

Even though the end of the barrel is faced flat notice that the edge of the bore is just slightly broken and then lapped smooth.

[Arbalest]

Dont know about the one you're working on but many Air Rifle barrels are choked and should be only be shortened from the breech end. Shortening from the muzzle end has ruined the accuracy of some rifles I've read.