Adjustable Shotgun Comb Options

’ve I been gunsmithing for 40 years and one popular job I still receive often at my shop (Rustblue Gunsmithing, Rust Bluing. com) is installing adjustable combs on stocks. I’ve covered this before, such as in my "Shotgun Adjustable Comb Installation Tricks" article (December 2017). One important concern is the problem with installation of an adjustable comb on stocks with large hollow spaces around the stock bolt.

Here is a brief reminder: To fabricate an adjustable comb the top portion of the stock has to be cut for installation of the hardware, which allows for this piece to be adjustable in four directions—updown and left-right. Often this cut opens a bolt tunnel that allows needed movement of the adjustable comb but doesn’t provide anything to attach the base to because of the hollow space underneath it.

Installation of any popular Graco Corporation (Graco-Corp.com, or Stock Positioning Systems (Stock Positioning. com, hardware for 25" is milled for the installation of an adjustable comb allowing up-down and leftright adjustment, such as the SPS base. However, now there is nothing to attach the base to because of the hollow space underneath it. 25" thick. adjustable comb requires permanent attachment of the base above the stock bolt.

There are ways of installing these bases in the empty space such as by side gluing or other fixes. However, the deepening of this space by 0.25" down to allow movement often interferes with the stock bolt and creates an obstacle for manipulating it for gun disassembly or even tightening a loose action.

My usual fix (described in the article mentioned above) uses a much thinner base and provides more space for bolt manipulation, however, this base also has to be permanently attached to the tunnel area and solves the problem only partially. The perma nent installation of a base into certain stocks creates a major problem for accessing a stock bolt. Tired of this problem, I have decided to change from the traditional approach.

Instead of using a permanent attachment of the bases to the tunnel area, create a base which is designed to be removable and can be easily taken out for manipulating the bolt and then easily put back. This new approach completely takes away the concerns about the major problems with installation of the base in an empty space and leaving an obstacle for the stock bolt.

Aluminum Square Tube 6063-T52-Extruded serves well. The stock comb hardware attaches to the square base, which in turn is secured by screws from the side of the stock. After some search I have chosen a square aluminum profile with a specific size: 1" x 0.125" Aluminum Square Tube 6063-T52-Extruded. The square tube is sold by various metal providers and a size of 1×1" is convenient for installation into the stock after milling the tunnel with a 1" mill-cutter to the depth of an inch.

The idea is to fabricate a base-part which, as usual, enables four ways of comb adjustment but also is easily removable from and then put back into the stock. Milling a stock for the ready part is an easy, one-step operation with a 1" cutter to 1" depth. The length of the tunnel can be chosen according to the length of the stock and is not critical. The posts and bushings for the comb adjustment can be used as provided from the Graco or SPS kits, but I normally make my own.

The comb hardware is attached to the aluminum square and the square modified to secure the comb. Screws secure the bottom attachment inside the tunnel of the stock. This is a preferable way to do it as completely hides these screws. However, if this bottom attachment is not what you want, as an alternative the part can be attached with side screws through the stock’s side instead.

Conclusion This provides another option for mounting an adjustable comb base designed to be removable and can be easily taken out of the stock and easily installed back as needed using a square internal base secured to the stock tunnel’s bottom or through the side of the stock. This way the problem of interference between the stock bolt and permanently installed base is totally eliminated as parts can be taken out of the way as needed.

This is quite convenient as the base is just a modified square tube that is readily available. In some cases, the stock bolt can be reached through the tube without removal. AG