September 23, 2010
We're a strange lot...no doubt about it. As gun owners and users, we regularly want the impossible and can get darned upset when we don't get it.
We want high-powered rifles that'll shoot a heavy bullet with an absolutely flat trajectory out as far as we can see with benchrest accuracy and no recoil. We want handguns capable of knockin' down an enraged grizzly with one shot yet, at the same time, allow us to spend a pleasant afternoon firing hundreds of rounds plinking at tin cans. We want semiautomatic shotguns that'll digest every possible loading from 3-inch magnum duck loads to Uncle Fred's super-light, teach-the-kids-to-shoot, half-ounce clay-bird loads.
If you think I'm exaggerating, just talk to some of the folks in the booths of the major gun manufacturers during the SHOT Show or NRA Annual Meetings. They hear this sort of thing on a regular basis.
Among the most persistent complaints and requests I hear from shooters relates to shotguns and shotgun loads. I can't tell you the number of times I've had customers come into my shop with concerns about their semiauto shotgun not digesting this or that particular load. Invariably they thought there was "somethin' wrong with the gun."
I see this most often with the Remington Model 1100. It's certainly not because of any mechanical failing of the ol' 1100. Nope, the 1100 is one of the truly great shotguns of the 20th century. With the 1100, Remington has produced one of the finest autoloading shotguns ever designed and has done so at a price that put this gun in the hands of millions of shooters. Since the 1100 was introduced in 1963, around four million of these guns have been produced. That in and of itself is just incredible.
The upshot of the amazing popularity of this gun is that it gets a lot of criticism that's not warranted. For example, take the issue of using light loads.
The 1100 is a gas-operated shotgun. Upon ignition of the primer, the powder is converted into a gas. This gas expands at an incredibly fast rate and pushes the wad and shot out of the shell and down the barrel. As soon as the wad passes beyond the gas port or ports, some of this gas is diverted through the gas port into the gas cylinder. The pressure of the gas builds up and pushes the gas piston along with the action-bar sleeve back towards the receiver. As the action bar moves back through a series of mechanical links, it disengages the locking lug, unlocking and opening the breech bolt.
As the breech bolt moves to the rear, it automatically extracts the fired shotshell and releases another shotshell from the magazine into the carrier. It then activates the carrier, raising the unfired shotshell so it can be loaded into the chamber. The breech bolt continues back into the receiver, compressing the action spring. Once it reaches the end of its movement, the compressed action spring pushes the breech bolt forward, chambering the next round. It's a fairly simple process.
Many of the problems I've seen with the 1100 were caused by the gun owner. The one I've seen most often is the incorrect assembly of the gas-piston seal, the gas piston, and the "O" ring or barrel seal. The gas-piston seal has one flat side, a groove in the center, and a bevel or taper on the other side. It's installed over the magazine tube with the flat side against the front face of the action-bar sleeve. The gas piston has a taper on one side and a reduced diameter step on the other. When installed, the taper on the gas piston matches and fits into the taper on the piston seal. Finally the "O" ring is placed on the magazine tube and pushed rearward until it's seated in a circular groove in the magazine tube. The barrel is then slid on the tube, completing the assembly of the gas-cylinder components.
Reversal of the piston or piston seal will cause major problems and lead to malfunctions. A trick I learned years ago is to make sure the slots in the piston and piston seal are not aligned. If the slot in the piston seal is positioned at, say, 9 o'clock, then the slot of the piston should be at 3 o'clock. If the slots are aligned, gas will leak from the system and cut into its efficiency.
The "O" ring is often stretched, mashed, or damaged in some way. Many folks are not as careful installing the "O" ring as they should be, and they inadvertently damage it. A damaged "O" ring will allow gas to leak out of the system and make it more difficult for the gun to operate properly.
For the gas to get to the piston and piston seal, it has to pass through a vent or port in the barrel. Depending upon the type of barrel, there may be one or more ports, and these ports can vary in size. The ports can and will clog up over time with carbon and plastic wad fouling. As the openings in the ports foul, they become smaller, and less gas can be vented into the gas system. For high-pressure loads, that may not be a problem, but for light loads, that can often make the difference between functioning and malfunctioning.
While most shooters will do a good job of cleaning the inside and outside of the barrel, many never think to clean the gas ports. If you have a set of drills and a pin vise, that's all you need to clean the ports. First, find the drill bit that will just pass through the port into the barrel. Install the bit in your pin vise and use it as a reamer to clean carbon or plastic fouling from the port. Be careful not to scratch the inside of the barrel with the tip of the bit. As you turn the bit by hand, you'll be able to tell if you're scraping out fouling. With just light finger pressure, you shouldn't have to worry about enlarging the port.
Speaking of enlarging the gas port, a lot of folks want to do just that to solve any functioning problem. Generally, that's not a good idea. True, you can open up the gas port and vent more gas into the system. However, what happens when you shoot heavy loads through that same barrel? You vent out more gas, and this can cause severe wear and tear on your gun. I've seen guns that were literally battered into junk because someone thought, "If some gas is good, more gas is better!" Friends, this ain't chocolate cake or grandma's cookies. More is not necessarily better, and it can sure cause severe problems.
Opening up gas ports in a barrel should only be done with a complete understanding of the consequences and what ammunition will be used in that barrel hence forth and forever more. It's a rare situation where I'll open up gas ports, and I urge anyone thinking of doing so to exercise extreme caution. It's awfully easy to get into trouble and ruin the barrel or the gun.
Two areas that can have a major effect on the proper functioning of an 1100 with light loads are, believe it or not, the inside of the action-spring tube and the magazine tube. The action-spring tube is located at the rear of the receiver and houses the action spring. That's the spring that pushes the b
olt back into place against the face of the barrel. I have seen a number of guns where the inside of the action-spring tube was just plain filled with dirt, rust, gunk, carbon, bits of weeds, and other assorted debris. Anything that will inhibit or slow the movement of the action spring can cause a feeding malfunction.
The same holds true with the inside of the magazine. I have seen more than one 1100 with the inside of the magazine rusted and the magazine spring rusted to the point that the spring wire had broken. This obviously would make movement of the shells out of the magazine difficult if not impossible and would lead to feeding problems. Many times, the owner incorrectly thought the feeding problem was caused by something in the gas system.
One other "cause" of problems with light loads is the use of a barrel designed for a heavy load. A barrel designed for 3-inch magnums will have a single, small gas port, while a barrel set up for standard 23„4-inch field or skeet loads will have two larger ports. The magnum barrel will vent out less gas because it's under greater pressure. If you use light loads in that same barrel, you'll not get the amount of gas you need for proper functioning.
While it would be great to have a semiauto that would function reliably with every possible loading under every conceivable condition, it isn't likely to happen. The Remington 1100 is a great old gun, but even it can't do the impossible. Given a little care and attention, it'll come darn close, though.
Until next time, good luck and good gunsmithing!