The NMLRA

View Original

An All Around Gun | Building a Swivel Breech | Muzzle Blasts Archives

This article appeared first in the November Issue of Muzzle Blasts Magazine in 1990. NMLRA Members can read this and every other article ever published. Sign up today

AN ALL-AROUND GUN

by Tim Hamblen

Indiana

The idea for this gun came to me on a deer hunting trip in November, 1985, while canoeing down the flooded Muscata­tuck River in southern Indiana in pursuit of whitetail. I had seen several does, but no bucks. It seemed, however, that in every other tree there was a squirrel. Normally, our gray and fox squirrels are very shy, but a week of being trapped by flood waters had made them careless. A squirrel shot by a .54 caliber muzzleloader, though, is a total waste, so I began thinking that I needed a combination gun of some sort ... an ancient version of the Stevens over/under ... hm-m-m-m. I have always been interested in multi-barreled guns, especially swivel breeches, and so,I  decided that's what my combo-gun would be. When I got home, I began a search for all the articles and pictures of swivel guns I could find. After hours of reading, sketching, and figuring the smallest detail on pa­per, I started the toughest gun I have ever built.


There are few, if any, swivel components commercially available, so most mechanical parts must be made. I be­gan with the barrels, and this is where my gun is like no other I have seen. gauge, straight octagon, both from the now-defunct Montana Rifle Barrel Company. This odd marriage ne­cessitated a lot of planning and calculating. Figure 1 illus­trates the dimensions needed to compensate for the difference in barrel widths, and to make sure both friz­zens come up in proper alignment with the 'hammer when the barrels are rotated. Notice that the pan and frizzen on the rifle barrel are made wider to allow for this align­ment. I purchased the pans, frizzens, screws and springs from Dixie Gun Works in Union City, Tennessee. I made my own plates from 1 /8" steel using a design found in an old book. The pans were silver-soldered to the plates and the frizzens and springs then installed.


The first step in joining the barrels was by cutting a dovetail across both barrels (Figure 2). These were made by clamping the barrels in the vise, making sure they were level and square to each other and that the breech ends were even, then making the cut across both barrels. Once the dovetail was finished, a tenon was made to slide into the dovetails of both barrels. The tenons were made to fit somewhat loose in one of the barrels to allow for heat expansion while shooting, which could alter sight align­ment. The stock, once the barrels are installed, will tighten any lateral movement of the barrels. 

The next job was to make the breach plate.  I used a piece of 114" steel bolted to the barrels with 1/4 -28 machine screws, which are threaded into holes drilled into the ends of the breech plugs. (Figure 3). The next step was to weld a 3/8 -16 stud onto the breech plate so that its center is on the exact center of the combined barrels. Drill and counter­sink the hole for the stud, weld in the stud, then grind off any protrusions and weld slag. Reinstall the plate and file it to match the top three flats on each barrel, leaving excess metal on each side for fitting of the forward lock plates. Work these two sides down until each pan fits snugly against the barrels. When a good fit is achieved, attach the plates

The with tang a screw plate is into made the breech from plate. another piece of l/4" steel, with a hole drilled for the 3/8" stud. This bole must be a good fit. Now, cut the plate in the same dimensions as the overall measurement of both barrels for the height, and the overall width of both barrels with the forward lock plate installed. (Figure 5). An appropriate tang and trigger plate are now fitted and welded on. A 3/81' nut with a lock screw tightens and locks the swivel assembly together. (Figure 3).

I purchased a fine  English back action lock (also from Dixie Gun Works), then made a new plate of appropriate style using a piece of 1 /8" steel. As most shotgun style locks have a short sear arm, this one was lengthened by silver soldering an extension onto the arm. I used a large Siler flint hammer by reshaping the tumbler hole to fit the back action lock. The lock is held in place by a dovetail in the tang plate, and a 10-32 screw through the stock and threaded into the side plate.

I chose to lock the barrels  by means of a slide button on the side plate, which was a feature on a lot of old swiv­els. This slide goes through a slot cut in the side plate and is attached to a plunger inside. This plunger goes through the tang plate and 1/8" into the breech plate. A spring was installed between the slide and a support guide at­tached to the plate. All of the holes and the plunger must be square to prevent slop in the barrels. (Figure 4).

I decided on a simple trigger so I could use the  gun in primitive smoothbore matches which prohibit set trig­gers. I then altered a trigger guard purchased from the Log Cabin Shop in Lodi, Ohio, to fit the swivel. The guard is attached by a screw at the front which is threaded into the trigger plate, and the tang screw coming down through the wrist from above.

I browned all the steel parts with  Clorox (R). The bleach is used like most any browning agent, it just takes longer. De­grease the parts, apply the bleach with a swab and let it set for a day or two. The parts are then carded with steel wool and more bleach applied. This procedure is repeated until the desired finish is reached. I killed the rusting process by heating the parts and applying liberal coats of used motor oil. This gives the parts an antique-looking finish.

A fine piece of curly maple was supplied by a good friend, Mike Money of North Vernon, Indiana. This wood came from one of the last lots of gun wood worked up by the late Don Walp, known to many of the old timers at Friendship. Mike was able to obtain a truck load of this fine southern Indiana maple.

A chromic acid stain was used, as well as a coat of potassium perman­ganate. A hand rubbed oil finish completed the project.

An occasional tightening of the action is needed to keep everything in good repair, but I believe the ef­fort is worth it to have a one-of-a­kind, all around gun.


Muzzle Blasts on Instagram 

NMLRA on Facebook

NMLRA on Youtube

Muzzle Blasts Podcast

See this gallery in the original post