How to Crown and Chamfer a Rifle Barrel Muzzle
Russ Chastain 10.08.19
If your old faithful hunting rifle suddenly starts slinging slugs hither & yon, it might be time to check the crown. Any number of things can cause crown damage, including steel cleaning rods or allowing it to contact other hard objects such as stones (say, if you slip while hunting). When buying a used rifle, always closely examine the crown for any signs of damage.
In this tech video from Brownells, Steve Ostrem shows viewers how to crown a rifle barrel. What’s the crown, you ask? It’s the extreme forward end of the rifling out at the muzzle, and because it’s the last place the bullet touches before it leaves the firearm and begins its flight, any imperfection can cause accuracy problems.
Steps involved in re-crowning a gun barrel:
- Use a hacksaw to chop it off ONLY if the rifling is damaged down inside the muzzle
- Smooth it off with a file (if you cut it off)
- Square it off with a muzzle squaring tool (if you cut it off)
- Select the chamfering tool that matches your desired crown (narrow 45 degrees or wide 11 degrees)
- Select pilot to match your rifle bore size
- Lap it to remove fine burrs and scratches
- Smooth and/or round the outside diameter of the muzzle
It’s not that difficult… but I recommend examining the crown closely with a strong magnifying lens, to ensure good uniformity. I’ve cut a few crowns, and sometimes metal burrs can form next to the rifling lands… you don’t want that, so lap them off if they occur.
That’s about it!