September 19, 2011

Working the Remington Model 1100 Autoloader

The Remington 1100 shotgun has 95 moving parts, and it often inspires home repairs. That adds up to work for the gunsmith.

Since most of the Remington 1100’s 95 parts are moving, it isn’t uncommon to have a few 1100s in your shop for repairs at any given time. That sounds simple enough, but sometimes it isn’t. The gas-operated, semi-automatic shotgun has undergone a number of internal changes over the years, with a resulting variation in parts. Most of the parts will interchange with varying degrees of success. But gunsmiths must be aware of the changes that have been made, in order to be on the lookout for problems caused by improper parts that might have been used to “fix” this shotgun before it gets to your bench. This combination of factors can sometimes make it very hard to determine just what is causing a particular problem with an 1100.

To understand what we are facing, let’s begin by looking at this shotgun’s gas operation. It is important that a gas-operated firearm feed the gas cylinder/piston the right amount of gas pressure. Excessive gas will create unnecessary pressure in the piston assembly and lead to excessive wear and damage. This will affect the the overall performance and operation of any gas-operated firearm, and can be bad enough to be dangerous. Remington has changed the size of the orifices, the angle they are drilled, where they are drilled, the facing angles, and so forth in its barrels so many times that the manufacturer’s shop manuals carry over a full page—single-spaced and small print—of these changes, and when they were made. With such a wide variety of ammunition on the market, Remington kept trying to get the best gas-release combination to handle all. A 200-page manual would not be sufficient to handle all the possible combinations. Remington engineers also decided it was impossible to make the 1100 shoot both 2 3/4- and 3-inch shells satisfactorily, so they started making two different guns, magnum and standard. Most of these parts can be physically interchanged, but many will not work properly between the two versions.

Excessive recoil from an 1100 can be a sign of improper mating between the barrel and the rest of the gas system. Ironically, the problem can be caused by either too much gas pressure or too little. Excessive pressure will open the breech too quickly while there is too much pressure still in the barrel, allowing the breech to blow back so hard that it gives excessive kick. Insufficient gas pressure allows the breech to remain locked too long, giving the shooter the same recoil of a pump or other locked-breech shotgun. Swelling of the fired shell is a sign of the breech’s opening early and showing excessive gas flow. (Also check for an oversized chamber.) Low pressure often leads to a short stroke of the action. This will show up as improper or soft ejection and other feeding problems. Cleaning the gas ports will sometimes take care of this. Remington downplays the importance of the gas port variations, but will tell you they can create problems when changing barrels between different Model 1100s.

American Gunsmith Book of the Shotgun, Chapter 2

Courtesy Gun Tests Magazine

Field use of 1100-series shotguns leads to cleanliness problems, which contribute to feeding, extraction, and ejection difficulties.

Over 90 percent of repairs on the 1100s will be feeding, extraction, and ejection problems. As these guns get older, more and more parts become interchangeable, so look for a balance that will make the 1100 work right. As we take it apart, we will point out items that will help in your repairs of this shotgun. As you unscrew the magazine cap, always be prepared for the magazine-spring retainer to be missing from the shotgun you are working on. If it is, the magazine spring can shoot the cap more than 20 feet and damage whatever it hits. Even if the retainer is in place, the spring has been known to come out on its own after the cap is removed. With the breech half open, the barrel and forearm can be removed from the receiver, but these will not slip right out unless this is a well-worn shotgun. By wiggling and pulling the barrel and receiver apart, it is usually not hard to separate them. Some will stick, but they can be loosened by opening the breech bolt all the way back, pressing the release, and letting the bolt slam forward into the barrel. Doing this several times will drive the barrel forward out of the receiver. This procedure, unlike prying, will not damage anything.

The gas-piston assembly will sometimes come off the magazine tube and stick in the barrel lug, and sometimes it will stay on the magazine tube where it belongs. Always check the barrel seal to be sure the piston and piston seal are on right. I have had hundreds brought into my shop that were assembled wrong. The piston seal goes on first, with the flat base fitting snug against the front face of the action-bar assembly and the angle cut facing the muzzle. The gas piston goes on next, with its angle cut facing into the matching angle of its seal. The rubber barrel seal then goes on, and should fit the magazine tube very tightly. When slipped down to the notch in the magazine tube, it will still be tight. These seals need to be replaced if they are frayed, flattened, or stretched. Many owners will stretch these onto the front flat edge of the piston, or put them on in the wrong assembly order.

Remove the trigger assembly from the receiver by driving out the two trigger-plate pins and wiggling the trigger guard while pulling down on the trigger assembly. Look inside the receiver to see if the feed-latch bar is solidly staked into the receiver. Many of these will be loose and even fall out when you remove the trigger assembly. This is of little importance, because when the shotgun is properly reassembled, the front trigger-plate pin keeps it from moving around, while the trigger assembly holds it in its groove by putting proper tension on this spring. Staking the part back into place makes this shotgun easier to reassemble, but leaving it loose makes it easier to clean.

Pulling the operating handle straight out from the receiver will remove it from the breech bolt. If the gas-piston assembly is still on the magazine tube, slip it off, but avoid stretching the rubber gas seal. Grip the action bar, pulling it off the front of the magazine tube, to remove the action-bar assembly, the action-bar sleeve, and the breech assembly in one stroke. Before doing anything else, reach inside the receiver and push the link forward through the same path from which the action bar slipped.

It is usually unnecessary to remove the interceptor latch from the receiver. The interceptor-latch retainer was designed to be installed and removed with a special tool. This interceptor should fit tightly, with no wobble at all. Movement up and down should be smooth, and its spring must fit into the groove cut into the rear arm of the interceptor. This spring sometimes gets out of its slot and gets in behind the interceptor. This will keep the shotgun from feeding correctly, and can show up in nearly all forms of feeding problems, depending upon in which position it is holding the interceptor. Firing a shotgun with this problem can cause major damage to the 1100. The interceptor-latch spring is also staked into the receiver; it cannot be removed and replaced without metal damage to the receiver. Most 1100s have a fore-end support assembly that clips over the action bar, but earlier models did not have this part. Do not try to install one if it does not need it.

The action-bar assembly also varies. The two most common complaints from owners are that the operating handle comes out too easily and gets lost, or that it sometimes is too hard to get out. It is the operating-handle plunger that holds it, and this is part of the action bar. Some of these have a removable retainer and some are solid.

Before tightening this operating handle, talk to the owner and find out what he expects. I tightened one for a man a few years ago, and he brought it back a few days later. His exact words were, “I want it tight while I am hunting, but I want it to come out easy when I get home to clean it.” He was not kidding, and could not see why a gunsmith could not make it that way. If it needs to be tightened, and your action bar assembly has a removable operating-handle plunger retainer, remove the retainer. Put it on your drill press with a bit 1.5 times larger than the hole, and very carefully open up the cone-shaped hole with the retainer upside down. A little goes a long way, so make sure it is just a small amount. When reassembled, this will make the operating handle fit tighter.

The solid bars have a small hole on their undersides that goes through to the bottom of the operating-handle plunger. You can take a small punch that goes through the hole and drive this ball (plunger) a little further out the top. Again, a little bit does it. If you drive it too hard, it will break through the top of the action bar, and then you really have problems. Before you do anything, make sure the plunger and its spring are clean and working freely. Also check the cup-shaped hole on the bottom of the operating handle. Some 1100s have a slot cut into the rear of the operating handle, and the plunger is in the rear of the action bar assembly rather than on the bottom. They still work the same way, just from a different location. Make sure the operating handle is cut or slotted to fit the bar; it may have been changed as we discussed earlier. Next, check the slots or cup-shaped hole in the bottom of the operating handle to make sure they are clear and clean. Slip the handle into the action bar and see how much play it has. If it is too loose, tightening up the plunger will not make it work. In this case, replace it with one that is thicker. If it is tight, but still comes out too easily, the operating-handle plunger is not holding it tightly enough. Using a drill bit the same size of the cup-shaped hole, clean the hole. Just polish it with the drill tip; do not try to cut it deeper. If you cut this hole deep, the plunger will pop up into it, and the operating handle can not be removed. That is the end of a good shotgun, because it can not be disassembled again. Always try it before reassembling it inside the shotgun.

The breech bolt itself is easy to work on, and you should check the travel of the firing pin before taking it apart. With the locking block pushed up, the firing pin should move easily into firing position. With it down, this locking block should block the firing pin from reaching a primer. Remington has boxes full of homemade and incorrect firing pins that have been taken out of 1100s returned for factory repair. We have seen several that have had their front collars ground down by people with the mistaken idea this will stop the shotgun from misfiring. They believe this will allow the firing pin to go through the locking block easier. What this will do is allow the shotgun to fire without the breech being properly locked, creating one blown-up shotgun and one hospitalized shooter. This collar was designed to prevent firing unless the breech is properly locked.

The firing-pin retainer pin is driven out from the top to the bottom. This releases the breech-bolt buffer as well as the firing pin and firing-pin spring. As soon as these come out, the locking-block assembly will fall out the bottom of the breech body. The only other parts in the breech bolt are the extractor, extractor spring, and extractor plunger. We have discussed dogleg extractors in previous issues, so we will not go into detail here. To remove the extractor, the plunger must be pushed toward the rear of the breech bolt and held there while the extractor is pulled straight out. Make sure the extractor plunger moves back and forth smoothly and forcefully, or it will not hold the extractor solidly enough to extract the fired shell. If you remove the extractor, always pull the plunger out of the bolt face. A small screwdriver or punch can be used to pull the plunger spring out. Make sure these are free of rust and are clean. Rust in the extractor-plunger hole can create ejection problems and ultimately cause the destruction of the breech bolt.

The action spring is hidden away in the 1100’s stock, and is often forgotten in the search for feeding/ejection problems and cures. The action spring and tube collect trash and moisture, as the link forces the action-spring follower down the action tube so fast that it creates a vacuum. This vacuum, along with the residue thrown off the bolt as it slams against the rear of the receiver, will suck trash, dirt, and water inside. The stock must be removed before the tube can be reached. It is necessary to put both the lock nut and washer back on this tube before reinstalling the tube nut. By pushing the action-spring plug up into the action tube about three millimeters, it is easy to slide the action-tube spring plug out the side of the tube. This permits the spring and follower to come out the rear of the spring tube. Always brush the tube out and check for rust, then lubricate it with a light oil. Heavy oil and grease will create a hydraulic effect that will slow the action and stop the gun from ejecting or feeding correctly. The magazine tube is also a place that collects dirt and water because shooters often load it with dirty or wet shells. If dirt or rust slows down the magazine follower, it may not push a shell out of the tube fast enough to feed properly.

We have saved the trigger assembly until last. Mixed or improperly fitted parts can really give problems. Remington trigger assemblies are coded to match specific receivers and are not to be interchanged. Start your trigger disassembly by using a small screwdriver to remove the sear spring. Slip the end of the screwdriver into the coils right behind the sear and pull it back. This will release the spring from the sear and allow its removal. The trigger-plate pin bushing can be gripped from the same end that the trigger-plate pin detent spring is attached, then pulled out of the trigger housing. You must drive the trigger pin out from right to left because it is directional. I have found some that have been installed backward. If it does not come out with moderate force, it may be in backward. These pins are made directional by three slots driven into one end to spread the metal and make them tight when they are driven into the trigger housing.

To remove the trigger assembly, take a small screwdriver and carefully pry up the front arm of the left connector just enough to lift it up and over the connector-guide lug made into the trigger-guard body. When this is lifted over the top of the lug, the trigger assembly can be lifted out the top of the trigger housing.

One of the most common repairs on the 1100 is fixing a stuck or broken safety. After the trigger is removed from the trigger housing, the safety can be worked on. The safety-spring retaining pin is above the safety and can be pushed out either way. Push it out with a punch, and hold your thumb over the spring hole while you pull the punch back out. You may have to use a small punch to pull the safety spring out of its hole. The safety-detent ball should fall out of the spring hole with the trigger housing held upside down. However, dirt and oil often hold it in so tightly that it will not come out by tapping and any other type of coaxing. When this happens, try working the safety back and forth until you can get the ball to move up enough into the spring hole to remove the safety. After the safety is removed, you can use a punch to push the detent ball out the bottom of the spring hole. After cleaning, a medium-weight oil is best to use on the ball as it is reinstalled. The medium-weight oil will create a better seal to keep the dirt out. If you need to make it a left-hand safety, just reverse the safety button when you reinstall it.The trigger assembly should be checked to make sure that both the right and left connectors are moving together with just a very small amount of play between the two. Both connectors should move up and down without restriction, and should not be filed or cut on in any way. Modifying the connectors is not the correct way to do a “trigger job” on the 1100. As these are stamped parts and sometimes have sharp edges, it is all right to use a buffer to remove these sharp edges. Sometimes the signs of buffing will make you think they have been ground on, but a careful inspection will show the difference between grinding of metal and buffing off sharp edges.

Removing the carrier from the trigger housing requires removing either the right or left trigger-plate pin bushings. Push the trigger-plate pin out the side with a punch that will go through the hole and keep the carrier in place. There are three powerful springs that now come into play in removing the carrier. The carrier-dog follower spring is released as the carrier is removed, while the hammer spring is contained by the disconnector arm. The third spring is the carrier-latch spring. It must be released slowly to allow the carrier latch to fold over the front of the trigger housing without a forward snap that might break it. If the sear locks solidly onto the hammer, you can push the hammer back into the cocked position and remove this spring from the operation. As the sear spring has already been removed, you do not want to do this unless the sear grabs the hammer solidly so it will not “fire” halfway through your carrier-removal operation. It is easier to put the trigger in a vise and use a screwdriver to hold the carrier-dog follower down while pulling out the punch that is holding the carrier in place. Let the carrier slip forward and up slowly; it will come free, and you can slowly release the pressure on the carrier-dog follower. If you cocked the hammer, be sure to release it at this time.

A small punch is used to drive out the carrier-latch pin. Remember, this is a tough little spring, so hold the carrier latch firm when it is released. Use the same punch to drive out the carrier-release pin. Each of these parts should be checked for damage or modification. If any are to be replaced, check the new part against the old one for size and detail, remembering what we said about all the changes Remington has made in this shotgun.

Some of the more common problems are stuck carrier-dog followers, which will lead to failures to feed. A bent carrier latch will not lift a second shell to the chamber when the shotgun is fired, even though it may work fine while working it by hand. When the carrier dog is worn or loose on the base of the carrier, it will get the shotgun out of proper cycle and jam the action. If the front edge is worn excessively or bent, it will keep the trigger from engaging as it supposed to, and will create jams. These front edges are hand fitted in the Model 1100, and will vary greatly from shotgun to shotgun. If you need to fit one, leave a little extra metal on the front edge, taking off a little at a time until it is working correctly. It is very easy to go too far with this, thinking you have removed hardly any metal at all. There is a lip or tongue that sticks up, about one inch back from the front tip of this carrier. The size, shape, and height of this lip is also very critical, but, unfortunately, it is one thing that often gets bent or filed by someone who does not know what he is doing. Here’s what usually happens: This lip lines up with the action bar. If everything is not in proper alignment, the lip will keep the carrier from moving far enough to load the shotgun easily. Someone looks in and sees that by bending this lip the carrier will let the shells feed in easily. The problem created is that they now feed in when the shotgun is not properly closed and locked. Some people grind the lip down to just get it out of the way, which is akin to cutting your head off so you do not have to shave or get a haircut. When this has been done, the shotgun will not work correctly until a new carrier is fitted. To make it more complicated, there are more than 20 different carriers, each of which must be ordered by serial number. I would never suggest that a parts supplier could make a mistake, but comparing the new part to the old one before installing it might save you a lot of time later on.

The 1100s have good triggers for automatic shotguns. Light triggers will cause the shotgun to fail to cock on occasion, or worse, to double fire. Fully automatic 12-gauge shotguns are a shock to the shooter who is not expecting it. A light stoning of the sear notch on the hammer and the same on the sear will smooth any roughness that needs to be taken care of. Removing the sear from the trigger housing can only be done after removing the carrier-dog assembly from the trigger housing. The sear-pin hole does not go all the way through the trigger housing. It only goes through into the inside of the carrier-dog follower hole. You can reach into the carrier-dog follower hole at a 45-degree angle with your punch, and push the sear pin back enough to be able to grip it on the other side to pull it out.

Removing the hammer is a different story, because most 1100s rivet the right end of the the hammer pin so it will not come loose when the shotgun is fired. Be very careful if you try to drive this pin back through with enough force to fold in the riveted end through the trigger housing. This trigger housing is a cast-aluminum body and will break easily. The trigger housing is also very expensive to replace, and must carry the same code as the one that was broken. Remington does not like to pass out restricted parts, and prefers to fit these in-house. Drilling these out is also tough because their riveted ends are always thinner on one side. This makes your drill go to the side and off into the soft aluminum unless you are very careful. If you do get the old one out, do not try to reuse it, if it is weaker than it was before it was removed. This pin receives a lot of shock and vibration, and will work its way loose unless it is strong and well locked in. If one end of this pin is loose when the shotgun is fired, it will break the trigger housing, and you will have an expensive repair on your hands.

The 1100 generally has the same types of external features as other shotguns and its ribs, beads, stocks, forearms, and the like need the same maintenance and care. Broken forearms are common on this shotgun, because the wood, even though it is reinforced by fiberglass, is so thin that it cannot take much abuse. Stocks are often replaced on these shotguns without the stock-bearing plate being properly reinstalled between the receiver and the stock. This creates chipped or broken stocks that must be repaired or replaced. Leaving off the action-tube spring nut washer or lock washer prevents the stock from properly fitting.

All too often, someone will bring you a stock they have cut too short, and the tube nut sticks out past the cut stock. If it is only a small amount, you have some options. You can drill out a space in the recoil pad, taking care to not to go too deeply, or the shooter will feel the tube nut when firing the shotgun. The tube nut itself can be cut into, since it is longer than it needs to be. Notch the edges and you can still screw it on the action-spring tube. Do not shorten the tube, as some have done, because the 1100 will not work without the full travel of the action-spring set. The 1100 just cannot have too short a stock; its design will not permit it. ★