Disassembly

Fox Sterlingworth - General Disassembly

This write-up covers general design and disassembly of a 12 gauge, Fox Sterlingworth, Philadelphia shotgun of about 1929 manufacture. It should be the same for all gauges. Details of internal parts and their disassembly may have varied in early Philadelphia manufacture and particularly later Savage made Sterlingworth’s, after Savage bought A.H. Fox in 1929 and moved manufacturing from Philadelphia, PA. to Utica, NY. The earliest of the Utica guns may have been mechanically identical to Philadelphia guns as existing parts were used up. These instructions do not apply to the Savage Fox Model B, which was not a Fox design, but a Savage/Stevens Model 311 with a Fox name.

The Sterlingworth action is a modified Anson & Deeley design and there were many variations among makers. The Fox action is shown below in diagram and cut-away.

NOTE: Avoid ruining screw heads. You will need a proper set of firearm screw drivers for this gun as all of the screws have fine to very fine slots. If you don’t have some experience in firearm disassembly or a strong mechanical inclination I suggest you not undertake disassembly of a Sterlingworth beyond stock removal. It is not for the novice or faint hearted. If cleaning is the objective, no parts replacement or repair, then I recommend no further disassembly, beyond stock removal. Sonic cleaning and solvent washes, followed by adequate lubrication should be all that is needed. The most troublesome part to remove and reinstall is the top latch mechanism. However, it is all exposed inside the receiver to easily access for cleaning in place.

Stock Removal

Unlike many other shotguns the Sterlingworth stock is not held to the receiver by a stock through bolt but is attached locally at the receiver. This attachment is a strong connection and noteworthy for the amount of wood it brings to bear against the receiver, as shown in the pictures below, offering superior resistance to cracks and breaks at the receiver / stock interface and wrist. The web of wood between the two wrist cheeks is even reinforced with a corrugated fastener to resist splits between the cheeks as frequently seen in other guns.

Removal of the stock is not intuitive and involves a partial disassembly of the receiver to accomplish. Rather than go into it I refer the reader to the A. H. Fox Collectors Association Inc. website for an excellent write-up by Mike Campbell under the tab, ”Mech/Styles/Factory Letters” and “Disassembly” on the drop down from that tab. This will get you through to the parts that are harder to remove and reinstall.

D.0 - Receiver Disassembly

Being unable to find any disassembly instructions beyond Campbell’s instructions I decided to compose these as I made my way through a Fox Sterlingworth, Philadelphia address, 12 ga. shotgun made in 1929. As already mentioned there are likely some difference between Fox and Savage design and parts. I believe they may be similar enough that this composition may be useful for either Fox or Savage made Sterlingworth guns.
Borrow align-items-center justify-content-centering a picture from Mike Campbell’s instructions you can see below what you will see when stock and trigger plate are removed. There are set screws in the middle of the sear pin and hammer pin. The sears, their pin, sear spring and screw would have already been removed in the stock removal procedure. The hammer pin, and its set screw, removes the same as the sear pin.

There are few pins and screws in a Sterlingworth to mix up in reassembly but I recommend that all parts be segregated according to position and make it back in their same original position.

D.1: Top Snap – Barrel Lever Removal

Once the stock, sears and sear spring have been removed you will have the receiver as shown below. Removal of the top snap lever mechanism is harder than it looks and there are 10 parts to the assembly.
Start with Part 1 – This is a barrel head screw that stops over travel of the lever. It extends through a clevis and is peened over on the threaded end. You must grind off the peened head to unscrew it. A Dremel tool and diamond burr works well. The clevis piece won’t come out yet.

With screw Part 1 out of the way the lever shaft will rotate giving better access to screw Part 2 and removes some pressure off the spring Part 2. This is a screw with a ball shaped end riding against a follower and spring that keeps the lever and barrel latch closed. Leave the screw in and go to the next step.
Remove the set screw in Part 3, there may be two of them. Screw off the round nut. It may take a pair of pliers to get it started, then is should screw off easily, but leave the nut just slightly threaded on and tap the nut and lever shaft out of the tang. As you tap it out, the head of Part 2 will ride off the follower and spring. Once it is clear, unscrew and remove Part 2. Finish unscrewing Part 3 and drive the shaft out of the clevis and through the upper tang.
Once the lever shaft is removed the clevis piece, at Part 1, will fall out. There are two more pieces to the mechanism hidden inside the receiver. These two parts are pictured below. Remember the tiny spring you removed under the trigger plate screw? That spring operates a pin, Part A, that rises through the receiver and can be seen just inside and to the bottom of the slot in the receiver face that accepts the barrel locking lug. Push it out through the bottom of the receiver in the direction you removed the spring. The other piece, Part B, is enclosed up in the receiver and behind the lever shaft. It is the barrel lock and rotates through the lug to hold the barrel closed to the receiver. The pointed end of Part C , the clevis, inserts into it. Gently tap this piece out to the rear with a punch from the slot in the receiver face. It should come out easily. You will see that the hole through Part B is not in the center and must be reassembled with that hole aligned with the point of Part C.

When finished disassembling all the parts and pieces to the top snap mechanism these are the parts you will have and more or less how they reside in the gun. Keep them all together.

The left picture below has the hammers reinstalled without their spring to show how they lie in the receiver and don’t come out when their pin is removed. The right picture shows the cavities in which the hammers lie and are locked behind a middle piece above the recess. This feature will help pre-position the hammers in place for reassembly.

The cocking levers and hammers are all one piece in this design. The cocking lever end is the narrow align-items-center justify-content-center part that disappears up under the forward part of the receiver as pictured above. To get the hammers out, pry the levers down, relative to picture, as if slightly cocking a hammer. You may have to wedge it down with something to get it to stay. While wedged down, insert the flat of a screwdriver blade between the top of hammer, the firing pin end, and the hammer recess of the receiver. Carefully pry the hammer up toward you, relative to picture, slide it up and rearward; hammer, spring and follower will come out. Repeat for the other hammer.
This completes the major disassembly of all the receiver parts. Whatever your plans are for reassembling the receiver, carefully and thoroughly clean all the recesses and holes before lubricating and reassembling the parts. Access to a sonic cleaner is great help.

D.3: Sub-assemblies

Now is the time to return to the subassemblies of the safety on the upper tang and triggers on the bottom trigger plate. Examine both carefully and you will see that both are very simple and straight forward.
The entire safety mechanism is held in place by one tiny pin through the under side of the safety button. Note for reassembly that the leaf spring under this pin has a pointed end. That pointed end will reassemble forward toward the front of the receiver and the bow of the spring up against the pin. The other parts can only go one way and are intuitive in reassembly. Keep all these parts together
The trigger plate has a bowed leaf spring which serves as the trigger return spring for both triggers. Remove the small screw at the rear end of the spring. Note there is a slight bow in the spring and the bow must be up, as you hold it, in reassembly. The triggers are both held in a slotted lug by one through pin. Drive out the pin and remove the triggers. Note which side, right and left, the different trigger shapes go in. The right trigger is the forward trigger and the left the rear. Keep all these parts together.

R.0 - Receiver Reassembly

Excluding sub-assemblies, like the safety, reassembly should follow the reverse order of disassembly. Some things won’t matter; others will if they get in the way of some other part. Whatever order things come apart is typically the best way to put it back together. If you have the receiver case colored, as I did this one, then it may come back clean or it may have charcoal residue in nooks and crannies. Assure that all the parts are thoroughly clean and lightly lubricated before reassembly. More is not better in lubrication; a light coat of appropriate oil or grease on the various parts is all that is necessary. Everyone has their favorite oil or grease and philosophy of where, or not, to use one or the other. That is up to you.
The typical convention for pin removal and insertion is remove pins left to right and reinstall them right to left. That is not always true and may not matter on a Sterlingworth given how the pins are secured to the receiver with set screws. You will also want to reassemble things right to left and be sure that all parts having a left or right go back into their original positions. Some parts, like the hammers, cannot go but on their correct side.

R.1: Hammer Assemblies

The last step in major component disassembly was the hammer assemblies and will therefore be the first to reassemble. I found in disassembly that even with the hammer pin removed the hammers stayed in their slots until pried out. There is only about 1/8” spring compression on a hammer in the rest or fired position. There are likely several ways to depress the hammer spring to get the hammers into the slots but this is the method I used and doesn’t use any special tool.

Starting on the right side, insert the right hammer spring, then its follower and last insert the hammer with its pivot pin inside the cone shaped recess in the follower. I recommend a tiny bead of grease inside the follower recess and a little smear on the side of the follower against the spring. Otherwise lubricate according to your beliefs. I used the hammer handle, positioned as shown in the left picture to force the hammer down under the mid-bar between the hammers. That bar will hold the hammer in place until you can fully seat it with the wood dowel by tapping it into the receiver until the hammer snaps into the firing pin hole.

At this point the assembly should look like this but the hole for the hammer pin will not be aligned with the receiver hole, but should be close.

Place the notched block over the hammer as shown left.

R.2: Top Snap, Barrel lock Assembly

This will be the most difficult step of assembly to complete. Look back at the disassembly photos of the top snap parts. They are laid out in the picture, approximately to their orientation in the receiver. The picture below shows the same parts, partially assembled as the go in the receiver.

The pointed ball pin in the picture above goes into the barrel lock drum shown below and locks the barrel down, also as shown.

Right and left here will be as viewed from the rear of the receiver looking toward where the barrels would be.

Part 8 will not be installed at this time but before the bottom plate is installed at stock assembly.

Part 4 goes into the receiver from behind and under the upper tang, with its open end toward the barrels. The mostly closed opposite, concave end with a small round hole is oriented toward the rear. The pointed end of Part 3 goes into this hole and into a shallow slot in the bottom of the drum. Look at how these parts go together before inserting them for installation.

Align the holes in Part 3, clevis, with the upper hole in Part 1 and thread in screw Part 2. Part 2 was peened in place originally which had to be removed to get it out. If screwed in tight with a little thread locker it should be secure without peeing. With the lever aligned in its normal position along the upper tang, Part 2 should be to the left.
Lubricate Parts 6 and 7. Insert spring Part 7 into the hole in the receiver to the right of Part 1 shaft at the location of the lower hole. Then insert follower Part 6 into the spring. Here is where assembly really gets tough. Spring Part 7 is extremely stiff, like a hammer spring, and very difficult to depress enough to get Part 5 installed. Short of making some special tool, which I may do if I ever do this again, I resorted to brute force and an assistant. As I held Parts 6 & 7 depressed in their hole my assistant screwed in Part 5, through Part 1, and far enough over the point of Part 6 to catch it. From there it wasn’t too hard to wriggle Part 6 into place as Part 5 was screwed in.
The last thing is to tighten, but not too much, threaded nut Part 9 and lock it in place with set screw Part 10.

R.3: Sub-Assemblies

At this point the triggers may be installed in the bottom trigger plate. The front trigger is on the right and the rear trigger is on the left, as they would be in the assembled gun. A small through pin holds the triggers to the plate. To the rear of the trigger is a small, curved leaf spring held to the plate by a screw. The curved tip of the spring must be pointed up on the trigger end to hold the triggers up to the inside. Tighten the screw and the triggers are done. A dab of thread locker on the screw is a good idea.
I failed to get a picture of the safety installation but, like the triggers, it’s pretty intuitive how the parts must go on. The slide bar has a roller on one end and a fork on the other. The roller goes to the rear of the tang and the fork forward and underneath a brad in the tang. There is no front/rear orientation of the safety button, but is goes through a slot in the tang and another in the slide bar. The curved spring goes in with the tips against the slide bar and the pointed end of the spring toward the barrels. Getting the pin in through the safety button and over the arch of the spring can be exasperating because it is so tiny.

R.4: Stock

At this point you are ready to put the stock back on the receiver but there are two more pieces of the barrel locking mechanism to go in first. I refer you back to Mike Campbell’s instruction for stock removal at the beginning of this procedure and the picture below. Follow his procedure in reverse but install these two pieces first.

This spring load pin, Part 8, goes into the indicated hole in the receiver pictured below. The rounded edge goes forward toward the barrels and the flat edge to the rear. This pin is the hold open for the top snap.

I may have missed some steps, lacked better pictures or failed to be fully clear but think you can find your way through disassembly and reassembly with the information provided.

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OE.0 Odds and Ends

OE.1 - Many parts are still available for the Sterlingworth and I suggest the following two. Reproduction wood is also available through several leading stock making companies.
https://www.gunpartscorp.com/
https://www.ahfoxparts.com/
OE.2 - Savage bought Fox in 1929 and at some point moved production from Philadelphia. The two Sterlingworth guns I have that were the basis of this procedure were both made in 1929 and bear Philadelphia barrel addresses. One is SN range 70K and the other 120K and there are minor differences between them. I am sure, up to some point in Savages ownership and continued production of the Sterlingworth, they were using Philadelphia made parts until they were exhausted. Engraving and placement between the two is slightly different. Also, my earlier gun has a stamped and formed sheet metal safety slide bar, with no roller and my later one has a milled slide bar as pictured below. I suspect the stamped slide bar was a later Savage part that was replaced in my gun. There may be variations in parts.

OE.3 – There aren’t many parts to the extractor and forend latch but thought it might be good to add a couple of pictures because those part do go in a specific way.