Gunsmithing: Shotguns. Patrick Sweeney
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The Mossberg features dual extractors, ensuring a firm grip on the fired hull.
The bolt rests on the bolt slide.
The Ithaca barrel is secured with a barrel extension that engages the magazine cap.
The Ithaca barrel is slotted for the extractors, and you must have the action open the remove the barrel.
When the action is opened, you can see the lifter legs.
With the magazine cap screwed down until it clears the barrel…
…you can pivot the barrel (with the action Open!) and remove the barrel…
Ithaca Model 37
Derived from the Browning-designed Remington M-17, the Ithaca has been a favorite of left-handed shooters for decades. It is also one of the fastest and smoothest-pumping shotguns around. It has in this modern age, a peculiar trait: It does not have a disconnector. If you take a loaded Ithaca, fire the round, and then hold the trigger back, it will fire each time you slam it shut. You can empty an Ithaca in an amazingly short time doing this. Whether you can actually hit anything except the ground or empty sky is another matter. Many pumps did not have disconnectors in the old days, and shooters learned to get their finger off the trigger while pumping.
…then unscrew the magazine cap.
Remove the buttstock before starting in on the action screws.
Today's shooter, pumping a shotgun with a disconnector, does not learn to get his finger off the trigger while pumping, and will often fire his second shot with an Ithaca before he is on the second bird or clay pigeon. I'm really fast with a pump, but I can't use an Ithaca at speed. I learned on a Mossberg 500, then went to a Remington 870. Every time I tried to speed up with an Ithaca, I ended up throwing shots between targets.
Unique among shotguns, when the Ithaca action is closed, the lifter rests above the bolt.
The Ithaca is light, tough and fast. The barrel is held in place by the magazine cap. Check to make sure the shotgun isn't loaded. Leave the action open. The Ithaca extractor rests in a slot in the rear of the barrel. If you try to remove the barrel with the bolt forward instead of back, you will be foiled by the extractor resting in its slot. You may damage the extractor, barrel or both. Turn the magazine nut towards the receiver, screwing it away from the barrel extension. The magazine nut has two small bumps on its side. These are the heads of the disassembly bar. If the nut is difficult to turn, press on a bump and you can push the bar out to the side. The added leverage of the bar, allows you to easily rotate the magazine cap. When the stud on top of the cap clears the barrel, turn the barrel a quarter-turn and lift it off the shotgun. The easy part has ended, and you will need screwdrivers to take the action apart. Before you can remove the trigger assembly you must take the buttstock off. At the rear of the receiver you will see two sets of screws. The upper ones, with their lock screws, are the pivot pins for the lifter. The lower one holds the trigger assembly in the receiver.
On the rear of the stock, remove the buttplate or recoil pad. With a large screwdriver, loosen and remove the stock bolt. Slide the stock off. You need to remove the buttstock first because while the stock bears against the receiver, it pulls tight to the receiver while attached to the trigger assembly. If you try to remove the trigger assembly screw without easing the pressure from the stock, you will gouge the screw slot and maybe even strip the threads.
The Ithaca magazine spring is shorter than expected, but it works just fine.
With the stock off, unscrew the trigger assembly screw and remove it. Pull the trigger assembly out of the receiver. Hold the receiver upside down on your bench. In the bolt carrier you will see a small spring-loaded pin that is visible through a window. With a small screwdriver, press this pin away from the operating rod. Run the slide forward and out of the receiver. (If you have not removed the magazine cap the slide will stay on the shotgun.) Unscrew the lifter pivot pin locking screws, then the pivot screws, and pull the lifter out of the receiver. Slide the bolt and its carrier rearwards out of the receiver. If they have not already fallen out, pull the shell slops out of their slots in the receiver.
Cleaning the magazine tube on the Ithaca is the easiest of all pumps. Rotate the magazine cap to unscrew it. The spring and follower can then be pulled out. A curious note: The Ithaca spring seems too short, but isn't. When you pull the magazine spring out of other shotguns you may find it 4 or 5 inches longer than the magazine. Ithaca springs are an inch or 2 longer, and yet the Ithaca never fails to feed. Use a stronger or longer spring if it makes you feel good, but don't go and replace the spring, thinking it has gotten weak and short.
Scrub the gunk off the parts and receiver interior. To reassemble, place the bolt onto the carrier, and slide them into the receiver from the rear. Replace the shell stops. Put the lifter in place, and make sure you get the curved are of the lifter towards the top of the receiver. Screw the pivot screws back in, and line up the notches with the locking screws. Tighten the locking screws in place. Push the bolt to the front. Place the trigger assembly in the receiver and tighten its retaining screw. Slide the forearm back so the operating rod goes into the receiver. Use your small screwdriver to press the catch pin aside, and slide the operating rod back until it catches the pin.
Tighten the stock back on, and replace the buttplate. Replace the barrel.
Winchester Model 1897
The '97 starts out easy, but gets difficult on the take-down models. On the non-take-down models, it is simply a bit of work. To remove the barrel and break the shotgun down for basic cleaning, look to the end of the magazine tube. On the upper left next to the barrel of the take-down models is the disassembly pin. Non-takedown models lack this pin. Press the pin down, and when it sticks out of the other end of the tube, pull it until it stops. Using the pin as a lever, rotate the tube a quarter-turn. Slide the tube forward out of the receiver, and then slide the forearm forward until it stops. Grasp the magazine tube and barrel right in front of the receiver and turn it a quarter-turn. Pull the barrel and magazine tube assembly off of the receiver. Leave the hammer cocked.
You will need screwdrivers for the rest of the disassembly. On the upper rear of the receiver, near the hammer, you will find the carrier pin stop screw. Unscrew it. Press the carrier pin out of the receiver. On the lower right side of the receiver, above the trigger guard, you will find the shell guide stop screw. Remove it. Press the action release button and hold it down. Use a screwdriver to pry the carrier down from the bolt until it has moved enough that you can pull it down and out of the bottom of the receiver.
To remove the bolt, use a screwdriver to loosen and remove the screw that holds the