Gunsmithing: Shotguns. Patrick Sweeney
Читать онлайн книгу.internals a complete coating of all parts, and let the receiver drip out onto a paper towel for a few hours or overnight. The gunsmith who taught me, Dan McDonald, said “Oil is cheap and rust is expensive. Coat the surfaces and let it drip,” Once the excess has dripped off, then reinstall the stock.
As with the single-shot, use a high-pressure grease to coat the hingepin. Ail side-by-side doubles, and some over-unders use a pin that passes through the receiver from side to side. Some over-unders (the Browning Superposed is an early example) use a pair of trunnions on the sides of the interior of the front of the receiver. Circular hollows on the sides of the barrel assembly ride over these trunnions. Grease both sides.
Pumps
The first pump shotgun to be seen in any quantities was the Spencer. It established the pattern for pump shotguns to come, being a hammerless model with a tubular magazine under the barrel and a front slide to work the action. The design was complicated and required intricate machining, making it more expensive than contemporary doubles. Economic difficulties put Spencer out of business and the remaining parts were marketed by Bannerman. An odd design, but one that enabled the shooter to clean the bore from the chamber, was the Burgess. Built just about when the Winchester design by Browning was coming onto the market, the Burgess differed from other pumps (and the 1897) in two ways: The pump to operate the mechanism was not up front, and it didn't come apart into two pieces. Taking a pump apart for storage and transport was considered an important part of its marketing. Shooters and hunters a century ago traveled to the range or the hunting grounds by horse, buggy, streetcar or bicycle. Even in the 1930s my father, who lived in the city, could take a streetcar to the edge of town to practice or hunt. The contemporary doubles came apart into a compact package. A pump that did not was at a disadvantage in the sales arena.
Early pump shotguns came apart right at the front of the receiver.
The operating handle of the Burgess was a sliding part of the pistol grip. It and the trigger moved back and forward to cycle the action. It seems odd now, but back then there was no established “right” way to work the action, and the grip hand was just as good as the front hand. The Burgess opened for cleaning and storage by a latch. Opening the latch hinged the barrel and magazine tube down, but they stayed attached. One very interesting feature of the Burgess was that it could be folded for storage while the magazine was loaded. By snapping it shut and working the slide, the shotgun was ready for action. The competing Winchester could not be stored loaded. As a ready weapon for bank guards, messengers and railroad guards, the Burgess had much going for it.
The Burgess company had a serious competitor in Winchester. By 1897, Winchester had the now-famous Model '97 on sale, and a take-down model was soon to come. His health failing, Andrew Burgess sold the patents and machinery to Winchester.
The takedown shotgun a century ago came apart in two pieces, the receiver and stock, and the barrel and magazine. It was strong, but expensive. To have a two-barrel set for your shotgun involved the cost of a magazine assembly, and fitting the extra assembly to the original receiver.
The front half was a package that required each replacement barrel have its own magazine tube. The result was expensive and heavy.
Not all shotguns back then came apart this way, but the story of the Browning A-5 is for later in the book.
The first pump shotgun that came apart by removing only the barrel was the Remington Model 17, designed by (drum roll, please) John Browning. The barrel used interrupted threads, and a knurled nut on the end of the magazine tube locked the barrel extension in place. Making replacement barrels for the Model 17 was easier and cheaper than the Winchester method, and replacement barrels did not require fitting. A shooter could have different barrels for competition, hunting and defense. If you ever run into a Remington Model 17, it will look oddly familiar. By 1933 Remington had dropped the M-17, as they had newer designs to sell. The Browning patents were soon to run out, so Ithaca stepped in. At the time Ithaca was a maker of double guns. But Ithaca redesigned the Model 17 action slightly, enlarged it to 12-gauge (the Remington M-17 had been a 20-gauge only) and have since then endeared themselves to left-handed shooters.
The economic advantages to barrel-only removal made the design the dominant one in the market. While not as compact when disassembled, the cost savings are worth the size difference.
The general instructions for disassembly are simple. Make sure it isn't loaded. Open the action and leave it open. To take your pump shotgun apart you will have to turn a nut on the end of the magazine tube. If it has been on for a long time, or was tightened down by a strong person, you may need assistance. Do not seek that assistance in the form of pliers. You will scar the magazine nut. Open your Brownells catalog and order their padded and curved shotgun disassembly pliers. With these you can take your shotgun apart for the rest of your life without marring it. With the nut loosened or removed, slide the barrel off.
On pumps using crosspins, press the pins out and slide the trigger assembly out of the bottom. On pumps using screws, you'll need properly fitting screwdrivers. With the barrel off and trigger assembly out, slide the forend forward. Depress the shell stops to slide the forearm and bolt out of the receiver. Specific instructions to follow.
To clean, scrub the interior of the receiver, bolt, trigger assembly and forearm rails. Dry and lubricate them. Reassemble.
The Remington 870
The 870 has been around since 1950. Unlike the earlier Remington Model 31, the barrel retainer is not a lug, but a ring that surrounds the magazine tube. The ring has made the 870 popular with law enforcement agencies, because by replacing the magazine nut with a tube, you can increase the capacity of the shotgun.
To strip and clean the Remington, make sure it is unloaded, the hammer is cocked, and the action is open. Unscrew the magazine nut. Slide the barrel forward off the magazine. With the drift punch, press the two trigger pins out of the receiver. Pivot the trigger assembly down out of the receiver. On the Remington 870 the shell lifter is attached to and spring-powered by the trigger assembly. Inside the receiver you will see two flat pieces of spring steel on the sides. These are the shell stops. When you gently ease the slide forward, the stops will keep the slide from coming out. If you try to force the slide, the operating rods may loosen the shell stops. Loose shells stops usually mean an 870 that will not feed properly. With your fingertips press one and then the other down to let the slide pass. Once out of the receiver, the bolt and its carrier plate will fall off the operating rods.
The Remington 870 bolt locks into an extension of the barrel. The idea was not new to Remington in 1950, but rather came from John Browning and the A-5 in 1898.
Scrub the powder residue off the bolt, carrier, the inside of the receiver and the parts of the trigger assembly. Lubricate everything. Cleaning the magazine tube requires removing the spring retainer. On older 870s the magazine spring is kept in place by a spring steel cap that is press-fit into the magazine. With a screwdriver, pry the cap upwards until it is free. Pull the spring and follower out and clean them. To replace the cap, press the spring into the magazine with one hand while compressing the cap into it. Tap it flush with a mallet or screwdriver handle. Newer 870s use two detents in the tube, and a plastic retainer. The retainer has two sets of grooves in it. One set passes completely along the sides, while the other stops. To remove the retainer, use a screwdriver that fits in the slot on top of the retainer. Press the retainer down and turn it one-quarter turn. Ease the retainer forward and it will slide out of the magazine. To replace it, line the full grooves up with the detents and press the retainer in. Give it a quarter turn and ease it forward.
For the first step of reassembly you will need to juggle four parts, the bolt, carrier plate, forearm and receiver. The easiest way is as follows: Place the carrier flat on your bench within arm's reach, with the bolt in place