Smith and Wesson K-Frame revolver barrel removal and installation

Swapping barrels on a Smith and Wesson revolver can be difficult, but with the right tools it can be a manageable job. In this post, we are going to swap barrels on a K-Frame revolver.

The contents of are produced for informational purposes only and should be performed by competent gunsmiths only. and its authors, do not assume any responsibility, directly or indirectly for the safety of the readers attempting to follow any instructions or perform any of the tasks shown, or the use or misuse of any information contained herein, on this website.

Any modifications made to a firearm should be made by a licensed gunsmith. Failure to do so may void warranties and result in an unsafe firearm and may cause injury or death.

Modifications to a firearm may result in personal injury or death, cause the firearm to not function properly, or malfunction, and cause the firearm to become unsafe.

For this project, I ordered the following items from Brownells:

Removing a barrel from a revolver is tricky. If you aren’t careful with how you hold the frame, it can crack, bend or break. Furthermore, most gunsmiths report the newer Smith and Wesson revolvers will often break when a barrel is removed so it is important to proceed with caution.

To support the frame during barrel removal, I use an MGW Revolver Firearm wrench. The wrench is two pieces, the aluminum frame, shown here, and a Delrin® plastic insert that is machined to match the frame.

The inserts come in one piece and need to be split with a handsaw. When you look at the contour of the frame in the insert, you see how thin some of the frame areas are and why caution needs to be used to prevent breakage.

The insert and revolver frame are both placed in the wrench. A top piece bolts onto it to prevent the outside of the wrench from spreading.

To remove the factory barrel, the pin, if present (found on older Smith and Wesson revolvers) needs to be drifted out. The barrel can then be held in a barrel vise. I use a Farrell Vise with the jaws reversed to the flat sides.

A little pressure on the wrench breaks the barrel loose. It can then be unscrewed.

To install the new barrel, I clean the mating surfaces and hold the barrel in a vise and turn the frame until the barrel is tight and hopefully aligned.

Sighting along the top of the barrel to the frame, you can see how tight the barrel needs to be. To adjust alignment, the shoulder of the threads on the barrel can be faced on a lathe or cut with a special tool from Brownells.

At this point the cylinder can be installed and the cylinder gap can be checked. As a rule, .005-.006″ gap is where you want to be. In this case everything worked out and I ended up with a .005″ gap. Again, if the tolerances didn’t stack this well, the shoulder of the barrel could be turned back on a lathe. In some cases, the forcing cone would then require trimming to get the optimal gap.

This K-frame had a pinned barrel. The pin passes through the threads. A hole needs to be drilled for the pin.

To drill the pin, I use a cordless drill with the appropriately sized bit.

After the pin is in place, the new barrel is installed. Everything functions well. This revolver is now ready to be refinished.