Problem Solving with “Slip-of-the-Step” Ejectors

Recently, a beautiful high-grade shotgun, made by W. W. Greener around 1910, came into my shop. The shotgun was without any means of extracting the used shells; neither the ejectors nor the extractors worked. You can see in the photo below that the gun is opened, but the used shells are still unmoved from the chambers. Disassembly showed clear evidence of a previous attempt to repair these ejectors. Obviously, this attempt was not successful; and in addition, it left the extractors completely disabled.

I believe it was done without a clear understanding of the principles behind this device. This article is about Greener’s ejector and its repair. W. W. Greener used several types of ejectors on his double shotguns, but this one is quite special since it is a direct descendant of the first successful ejector design on the side-byside shotgun patented in 1874 by Joseph Needham.

Interestingly, it was Needham’s idea to split the extractor in two halves to implement selective functionality of the ejector, which means that only the used shell is thrown out of the chamber. Needham’s design was based on the "slip-of-the-step" principle. This principle in turn stemmed from the early single-shot-rifle ejector designs.

Several years before Needham’s patent, such rifles as the Peabody, Martini-Henry, and many others with a falling block used a simple ejector activated by the block’s downward motion during the breech opening. If you look closely at the hinge-pivoted falling block, it is somewhat similar to the hinge-pivoted barrels on the shotgun. Needham noticed this similarity and applied it to each barrel as if it was two rifles put together.

He also connected his ejector with the mainsprings of the locks, so that the energy of the springs might be used for striking the ejector arms. Compression of the springs and the strike of the ejector arms happens in one cycle of the barrels opening. In 1884, Greener borrowed the idea and slightly modified Needham’s design, slimming it down. The real beauty of his mechanism is in its extreme compactness. It’s even hard to find any indication of ejectors on the gun.

Figure 1 shows all three parts of the gun where you would normally expect to see components of the ejector mechanism. None of them are present on the Greener gun. There are no rods protruding through the action or ejector hammers in the forend. The only visible parts that participate in ejecting, beside the ejector arms, are the hinged block (1) on the barrel lump and a pair of two small ejector levers (3). There are two invisible parts, however.

These are extensions of the hammers, identified as #6 in Figure 2, along with other parts. (The numbers of parts in the photo, Figure 1, correspond to the numbers in the schematic drawing, Figure 2, for easier reference. These W. Greener shotgun came into the author’s shop with non-functioning ejectors and extractors.

Here we see the forend, action, and barrels of the Greener shotgun. At the bottom of the photo, note the hinged step block (1), the slip step (2), the toes of the ejector levers (3), the cocking tooth (4), and the ejector arms (5). hammer extensions are the parts that actually slip off the step. I call the block (1) a "step block" to be consistent with the name of the whole principle, slip-of-the-step.

When the barrels open, the hammer extension (6) slips from the step (2) and hits the ejector-lever toe (3), which moves the opposite shoulder of the lever toward the ejector arm and strikes it. After that, the hammer extension stops at the cocking tooth (4). It will not be raised until the hammer is put on full cock at the last stage of the barrels’ opening.

Note that if the lock has not been used, and the hammer is still cocked, then no ejection will take place, since the hammer extension will be fixed above the slip step. One other interesting feature of this type of ejector is that it does not need resynchronization. Resynchronization is a major problem on double-gun ejectors, with symptoms varying from simple uneven shell striking to complete ejector malfunction.

This issue would require a separate discussion, but the point I am trying to make here is that slip-of-the-step ejectors cannot suffer from resynchronization, since the timing of strike is totally predefined by the position of the step. The interesting question now is: Why didn’t the ejectors work on this Greener despite the presence of both ejector levers in place?

As you can see in Figures 1 and 2, only the short toe This drawing illustrates the principle of the Greener ejector and its parts: step block (1), slip step (2), ejector lever toe (3), cocking tooth (4), ejector arms (5), hammer extension (6), ejector lever (7), and extractor rode (8). of the ejector lever accepts the strike of the hammer extension. This toe, as well as the whole ejector lever, must be hardened to a spring condition.

Such hardness will withstand stresses and bending forces developed by the hammer-extension strike. A much harder lever would crack, and a softer one would wear out quickly. The toes on both levers were absent, which makes me think that during a previous repair the levers were either annealed or not heat-treated at all. The solution in this case was to make new levers, and to pay close attention to proper hardening.

The old ejector levers (2) were replaced with new levers (1) made of Starrett oil-hardening steel. The floor plate is opened for adjustment of the new ejector levers. The toe of the ejector lever is marked number 1; number 2 is the bottom of the step block. Figure 3 shows the new and old ejector levers. The new ones are made with Starrett oil-hardening steel. First they have to be made with excess material in the toe area, because the toes have to be precisely shaped.

They have to be large enough to effectively transfer the strike of the hammer extension to the ejector arms, and they have to be small enough to move freely under those extensions during closing of the barrels. This shaping can only be done by gradual adjustment to the lever, with fitting tested on the receiver. Taking into account that the actual engagement of the levers with the hammer extensions is taking place inside the action, observation is somewhat problematic.

The solution is to take the floor plate off the action and observe the fit of the parts through the bottom of the action (see Figure 4.) As I mentioned before, the critically important part of this fix is to properly harden the ejector levers. The goal should be to reach a hardness that will be sufficient for withstanding stress and wear, but avoid brittleness. I chose to temper the levers to the hardness of a good V-spring.

The reason is that every strike bends the lever around its hinge, as shown in Fig- This photo shows the position of the ejector rod between the forend hook and the ejector lever. usually even shorter than on guns without ejectors. It’s easy to understand why. The ejector arms should have enough travel for acceleration of an empty shell to make it fly away. If the extractor advanced the ejector arms much further, they would not have enough of this travel.

Almost all side-by-side guns use the forend extractor hook (see Figure 1) for moving the extractor during opening of the barrels. On this particular gun, one more part was needed to transfer this move from the extractor hook to the ejector arms. It is the small rod (1) shown in Figure 5. Since the rod was missing, I had to make one, keeping in mind that it must be prevented from sliding in place when the gun is without the forend, to provide for an easy forend reinstallation.

For this reason, I milled out two slots; one for the forend hook and one for the upper parts of the ejector levers as shown in Figure 5. The front slot allows direct pushing of the ejector arms instead of pushing the ejector levers, which is more efficient from a mechanical standpoint. The repair of the Greener’s ejector was not difficult, but required careful attention during the shaping and heat treatment of the ejector levers.

There is no need for resynchronization after this fix, as other ejector types would require. That’s because synchronization is provided once and forever during manufacturing by the positioning step on the step block. ure 2. As a result, the area of the lever around the hinge hole is the most vulnerable to cracking. So what about the extractors? They should move the shells on each opening of the gun, no matter if it is fired or not.

Normally, the shells would be moved out of the chambers just a bit, enough to handle them. On guns with ejectors, this move is I