Cutting and Crowning a Barrel Without a Lathe

Sometimes a barrel needs to be cut down in length to make a handier carbine out of it. Hunters especially like to have a rifle they can get in and out of the truck with and not be hung up on seat belts or snagged on the steering wheel.

Most of the time, I like to use the lathe to do this but occasionally there's a rifle barrel that doesn't fit in the spindle bore of the lathe to cut and trim.The final trim length is going to be too short to fit the spindle and have enough sticking out to cut with a tool bit.

The crown I’m after today is a simple one designed for hunting rifles and NOT precision target shooting. This works well on bolt actions or pump actions since you’re not changing the dwell time of the bullet passing the gas port and exiting the muzzle. The gun will be manually operated instead of semi-auto gas operation, and you’re not changing gas port pressures.

Remington 7600 barrel

Such is the case with a barrel from a Remington 7600. I measure the length to be cut, and use a common hacksaw to bring it to the new length. In this case, we're going from 22" to 18". The spindle bore length of my lathe only allows for an 18” barrel length, and the solid barrel lug of the Remington 7600 means that only 16” of barrel will protrude through. So I marke and measure the new barrel length and carefully cut the length with a hacksaw. I dress up the saw cut on a belt grinder and get started with the crown. I always make sure to cut and recrown hunting gun barrels to a minimum of 16 1/4” to comply with the law. The rules state 16” for carbine rifles, but the extra quarter inch is left because you want to make danged sure you’re not building an SBR (short barrel rifle) without a Federal tax stamp.

Cleaning up and truing the muzzle

I clamp the barrel upright in the soft jaws of a vise, and color the muzzle with Dykem blue.

90* cutter

Using a pilot of the right caliber, I insert it into a large 90* cutter head with a T handle. I turn the cutter to make the muzzle a 90* cut to the bore.

11* recess

I keep the cutter moving to give smooth chatter free cuts until the Dykem is completely gone. This way I know the entire muzzle face has been cut. Plenty of cutting oil and a slow steady pace keeps the cutter from leaving chatter marks.

11* cutter

Next, I switch the pilot to a different cutter. This one will cut an 11* recess in the face of the muzzle. I turn this cutter until I get a shallow cut about halfway to the edge of the barrel. Again, the muzzle is degreased and Dykem blue is applied so I can see where to stop the cut.

Finished muzzle

The job is finished after I clean up the burrs and take the sharp edge off the outside diameter of the barrel with a fine file and Emory cloth. The inside edge of the barrel is also cleaned up with a demurring tool and Emory cloth. A couple good coats of cold blue matches the fresh cuts to the rest of the barrel so you leave nothing shiny behind.

A good muzzle crown is important to a rifle's accuracy. You want the bullet to release from the muzzle consistently between shots. Any irregularities would allow hot gasses to leak from around the base of the bullet upon leaving the muzzle, and cause the bullet to yaw to one side or another and throw off the shot groups.

There are a few different types of barrel crowns. Some are rounded, some are recessed heavily. This is a quick solution that gives pretty good results. Unless the customer is concerned about precision crowns, you can actually save the hunter some money by charging bench rate instead of machine rate on prices. And it can be done by hand without a lathe. A pump action rifle is going to be plenty accurate for hunting with this type of crown. You should always protect the crown of your gun barrel. Some hunters will stick the rifle muzzle down into the floorboard of their trucks, with the remaining gun itself resting against the seat. While this can be handy to have the gun ready at hand, you may bump the crown on small gravel that comes off your boots and into the floorboard. This could potentially damage the crown when you're driving on a bumpy dirt road. You could get a small ding on the crown and ruin the accuracy of the rifle.