Pre-Season Gun Maintenance Part 1: Gas Operated Semi Auto’s.

by Field Staffer Pete Lochner
September 4, 2008

Spring is gone, summer is here, which means duck season for some is only a short time around the bend. I asked Clay if I could write an article for the website about a subject near and dear to me, but that others hate, GUN MAINTENANCE! The first part of this article will be focused on gas operated Semi Auto’s being this is the most maintenance prone weapons system. As some of my closest friends will tell you, I am very anal about my guns, and that I could probably write a book on the subject. This article will hit the high points hopefully keeping your shooting stick functional and with you for seasons to come.

The first weapons system we will cover will be the “gas operated” system i.e., the new and popular Beretta Xtrema, the Browning, and Remington families. As most of you already know these guns rely on the gas formed as the shot is fired to function the slide so the next shell can be chambered. Without getting in too much detail, these guns have a gas piston of sorts with small gas ports, which the gun relies heavily upon to function. These gas pistons also have a gas ring which seals the gas piston, as not to allow the gas to escape into anywhere but through the gas ports. (See picture 1)

Having this information and understanding how this type gun functions will help us in conducting the proper maintenance. Knowing that your gun operates on this system, probably the most important part of your maintenance is going to be properly cleaning your “gas system “so that the gun will allow the gas to exit the gas ports in the barrel and enter, and exit the gas piston. Depending on how much you shoot each year will dictate the amount of “carbon” build up you will have on your gas piston. I would strongly recommend if you shoot everyday cleaning the “gas system” at least mid season, and then at the end of season, unless you notice the gun is malfunctioning. In that case the first thing I would do is check to see if the gas system is clogged and that the gas ring is intact. If the gas system looks as is if it is operational, then you may need to check with your gun smith.

BEFORE CONTINUING* WARNING MAKE SURE YOUR WEAPON IS CLEAR AND SAFE BEFORE CLEANING! DOUBLE AND TRIPLE CHECK FOR ALL CONCERNED! There are multiple ways to clean your gas piston and ring, a trick that I have learned is somewhat like cleaning a muzzleloader. Take a small bowl, put a small dab of dish soap, and then add some water, making it a soapy solution. Be careful not to overdo it with the soap! As you field strip your gun, remove the gas piston and ring first off. Place both the piston and ring into the solution and just let it soak. The dish soap will help dissolve and loosen the built up carbon. After cleaning the other parts of the shotgun, come back to the gas piston and ring, use a gun “utility” brush and begin scrubbing the piston and ring, making sure the gas ports in the piston are free of any carbon. Also note if you look down the barrel of your field stripped gun you will see two small holes on the bottom of the barrel, this leads into a housing that the gas piston seats into. (See picture 2) Make sure that these holes are also free of any carbon. Before assembling your gun, make sure the gas piston and ring are dry; you may have to rinse the piston in some hot fresh water to insure there is no soap remaining. Either let it air dry, or hit it with some air. I do not recommend heavily oiling the gas piston, this may cause carbon to sick and fowl the piston. Taking these extra steps in cleaning your gas system will greatly improve the function of your shotgun.

Next we need to make sure the barrel is clean using numerous different products on the market today, clean the bore of your shotgun. After cleaning it should look clear and shiny. If you notice any pitting or bulges in the barrel, you may wish to have this checked by a gunsmith, if the integrity of the metal is at all in question, do not fire the gun.

Now that your barrel and gas system are clean we need to move on to the bolt or “slide” if you will. If you have any question during these procedures please refer to your appropriate owner manual for disassembly and assembly of your shotgun. Depending on your comfort level, you may choose to just remove the bolt and clean it, or remove and disassemble the bolt for cleaning. At which ever you choose, the main key here is to make sure the bolt is free of carbon and any fowling. Use your utility brush, and maybe some gun scrubber to clean the bolt. The gun scrubber along with a rag will ensure that any old oil and fowling is gone. After removing the bolt, you now have a hollow receiver, use the same techniques as the bolt in cleaning. I also recommend canned air, or an air compressor on both, but if you do not have it available, an old rag will work to.

Now really the only thing you have left to clean should be the trigger housing, mechanically speaking. Usually your feed ramp is attached to the trigger assembly, and is removed by pushing out a couple of pins. You may need to use a punch to do this. The trigger housing may need to be hit with some gun scrubber and your utility brush should any fowling be on it. Your canned air or air compressor can be handy in cleaning the trigger assembly. Just be extremely careful if using an air compressor, there are many small springs which could be blown out if you are not careful! I usually lightly hit the trigger mechanism with Remoil after cleaning, before reassembly.

At this point, you should be ready to reassemble your shotgun. I highly recommend lightly oiling your bolt before reassembly, when shooting there is heat and friction on the bolt as the gun fires repeatedly. Depending on the temperatures where you hunt, it may be necessary to use a “dry lubricant” as to keep the bolt from freezing. There are numerous different oils on the market today; I generally will use Miltec on the bolt. In which ever oil you use, be aware that some oils are Teflon based, be sure to shake the bottle well, as the Teflon can and will settle on the bottom of the can or bottle.

When storing your shotgun, it will not hurt to put some Rig oil, or Remoil on the gun, just a light coat to prevent rust. When taking the gun afield use a rag to wipe the gun dry, as to not invite any unwanted dust or other environmental stuff on it.

Again if you any mechanical problems or maintenance questions, contact either a competent gunsmith, or the manufacturer of your shotgun. If you spend a little on some good cleaning gear, and time for maintenance, you will save greatly on buying new shotguns. I hope this brief maintenance article will help keep your favorite shotgun in good working order, so when the birds are flying, so will your steel.