Cleaning & Maintenance for SIG Pistols

John O. Stewart

The Short Guide

Note: Wear eye protection whenever cleaning or maintaining firearms!

Note: these instructions were written for traditional metal guns with traditional blued or nitron finishes. Extra caution when using solvents and mechanical residue removal methods should be used with plastic parts, including polymer frames, and colored sights, including night sights. Nickel and other plated finishes may also require special treatment. When in doubt, use only products and methods specifically designed and intended by the manufacturer for use on firearms, and follow all manufacturer instructions and recommendations.

1. Field strip the gun, to include removing the recoil spring and guide and barrel from the slide. It’s not necessary to remove the spring from the guide rod. If you do, though, remember that for SIG handguns “tight is right” when inserting the guide into the spring.

2. Wipe everything with a cotton rag or soft paper towel to remove loose dirt. Use solvent only if necessary; usually wiping is sufficient. A good cleaner for removing old, dirty lube is 91 or 99 percent isopropyl alcohol (available at most drug stores and many supermarkets). Alcohol should be used on metal parts only, not on plastic or sights.

3. Run a patch with a copious amount of bore cleaning solvent through the barrel and let it sit.

4. Unload, disassemble, and clean all your magazines. Brush or wipe off any visible dirt or debris. Run a rag or paper towel through the tubes and thoroughly remove any oil or other lubricant. Reassemble while making sure the orientation of the spring is correct.

5. Run a rag or paper towel through the magazine well. Don’t use lubricants or solvents.

6. Check to ensure the grip screws are tight; if you can turn them with finger pressure, they’re too loose. Tighten them with a properly-sized screwdriver (SIG pistols: snug plus 1/8 turn).

7. Push a clean patch through the barrel to remove the solvent. Brush it 10 times with the bore brush. Apply more bore cleaning solvent and let it sit.

8. Lubricate the frame and slide: rails, hammer face, and inside the slide where the barrel contacts it. Apply only enough lubricant (oil or grease) to see and feel it. If it runs anywhere, there’s too much: remove the excess.

9. With two or three clean patches, remove the solvent from inside the barrel. Apply a very thin coat of oil inside the barrel for rust prevention.

10. Lubricate the outside of the barrel, with particular attention to any areas with worn finish.

11. Reassemble the gun and ensure everything works as it should. That includes inserting the magazines to see if they lock in place, hold the slide open when they’re empty, and drop freely when the magazine catch button is pressed.

12. Apply a light coat of oil to the outside of the slide and “controls” (decocking lever, takedown lever, slide catch lever, trigger, and hammer). A silicone cloth of the kind that are sold in most gun shops or in the sporting goods section of places like Wal-Mart works well for this purpose. If you carry the handgun, wipe it down with a silicone cloth or a patch and a little oil at the end of every day.

That’s it - maybe 20 minutes. For more detailed information, read the long guide, but if you follow these instructions, the result will be 90 percent as good as the best that’s possible.

The Long Guide

These procedures were originally written for the officers of my agency who, like most other LEOs, don’t know much about guns and usually have even less interest in them except as a seldom-used tool of their trade. My goal was to prepare a “cookbook”-style set of instructions that could be followed by new shooters to achieve an adequate level of firearms maintenance. Knowledgeable and experienced gun owners may find them to be either somewhat simple and overly-detailed on one hand or that they’ve left out some things they think are important on the other. The thing to remember is that this is a guide, not carved-in-stone, the-only-way-to-do-things dogma. As with any guidance, users should make their own evaluations and judgments as they go along and decide for themselves what’s best for them.

In addition, it’s important to understand that one method of cleaning and maintaining autoloading handguns like the SIG Classic-series is not the absolute best for all uses that the guns may be put to. The emphasis of this guide is on cleaning and maintaining a SIG pistol carried for defensive purposes by police and others. If the gun is fired a lot, especially during long training sessions when it’s not possible to strip the gun and lubricate it during the day, extra lube at the beginning is a good idea. I live in a dry mountain climate where the record high temperature is less than 90 degrees and winter-like weather can be expected from September through May. Perspiration and other contributors to rust are not common problems. If you live where the humidity is high, where you’re exposed to salt sea air, or where high temperatures result in a lot of sweating, extra rust prevention measures will probably be necessary. A gun that’s used only on the range or kept in the house for defensive purposes can be left “wetter” than one that’s carried in a holster every day.

Finally, note that these instructions pertain specifically to modern production SIG handguns. Much of the guidance may be applicable to other guns, but some comments do not. If in doubt, seek information from the manufacturer of the firearm in question.

Sig Sauer Classic-Series Pistol Cleaning & Maintenance

Refer to the factory operator’s manual for a troubleshooting table and instructions on the proper method of field stripping the pistol for operator-level cleaning and maintenance. With the occasional exception of also removing the pistol grip plates (see below), further disassembly of the gun at the operator level is not required or recommended. If you do want to disassemble your gun further than field-stripping it, ask for advice on the SIGforum. Although disassembling Classic-series SIGs is easier than some brands, there are a few tips that make the job much simpler and will also help you avoid a couple of pitfalls that can cause serious problems. One of the best things that SIG pistol owners can do for themselves is to purchase the armorer DVD produced by Chris Willardsen and Chris Orndorff. It’s available directly from them though the contact information posted on the SIGforum, Brownells, or Top Gun Supply.

Inadequate cleaning and lubrication are the cause of most of the problems experienced with the SIG line of handguns. Whenever you fire your pistol, it should be cleaned at the first opportunity. However, despite the importance of ensuring reliability by cleaning a gun every time it’s fired, there’s another reason that’s seldom discussed, but is actually even more important.

When is a gun most likely to develop a problem of some kind - when it’s fired during practice or while it’s sitting in a safe or being carried in a holster? The answer is obvious: during practice. Field stripping and cleaning the weapon after every range session helps ensure that problems are detected as soon as they occur.

Cleaning Materials and Equipment

A basic cleaning kit should include the following items: Cleaning rod at least 4.5″ long (5-6″ is more convenient); bronze (not stainless steel!) bore brush of the proper caliber to fit your barrel; slotted cleaning patch tip; cloth gun cleaning patches of the proper size; toothbrush or similar brush with short, stiff bristles; gun cleaning solvent(s); gun oil and/or grease; and absorbent cotton rags or paper towels (I recommend Bounty or other good quality brand; the cheap ones tend to smear the dirt rather than absorb it).

Other items that are not absolutely necessary but can be very useful include a shaving brush or similar long-bristled brush; cotton-tipped swabs (Q-tips); wooden toothpicks; screwdriver to fit grip panel screws; proper caliber cleaning “jag” (a solid brass or plastic cleaning rod tip that holds a cleaning patch in tight contact with the bore of the barrel); and a cotton bore “mop” of the proper caliber.

SIG SAUER recommends that its guns be cleaned and maintained only with solvents and lubricants that are specifically intended for use on firearms. Solvents and cleaners which are not marketed by their manufacturers for use on guns should be avoided. These include various paint thinners and cleaners, ultrasonic cleaning compounds, and fuels like gasoline and kerosene. In addition to the obvious health and safety hazards that some such materials pose, they are usually much more effective at removing the lubricants necessary for the gun’s proper operation than they are at removing dirt and firing residues. Certain solvents may also damage or destroy the synthetic materials and finishes used in modern guns. Oils, greases, and other lubricants that are not intended for firearms may not provide protection for the unique stresses that firearms are subject to, may leave harmful or difficult to remove residues on the gun, damage holsters and other duty gear, or contaminate or deactivate ammunition.


The fundamental purpose of cleaning is to remove all foreign substances from the gun. This refers to firing residues plus perspiration, dirt, debris, and other contaminants that may have accumulated on the gun during routine handling and carrying.

Caution: Before beginning the cleaning process, unload the pistol and all magazines. Ensure that the weapon is unloaded by looking through the magazine well and into the chamber of the barrel. After looking, double check by feeling with a finger that the chamber is empty. Remove all ammunition from the immediate area so that you do not unthinkingly load the gun or magazines until the entire cleaning process is complete.

Wear adequate eye protection (like your shooting glasses) throughout the cleaning process. Escaping springs and splashing cleaning compounds can cause serious eye injury.

1. Field strip the pistol in accordance with the instructions in the operator’s manual.

2. Barrel. Cleaning the barrel is the most time-consuming process and therefore it’s recommended that it be started first. Note that the below sequence is a general one useful for a variety of modern solvents, but the best thing to do is read and follow the instructions provided by the manufacturer of the solvent you’re using.

Caution: Always read the instructions accompanying all cleaning compounds and lubricants. Some solvents can cause property damage or physical injury (including severe eye damage) if used improperly. Some very powerful solvents should not be left in contact with the gun, including the bore, for more than 15 minutes at a time. Again, read and follow the manufacturers’ instructions!!!

a. Wipe the outside of the barrel with a rag or paper towel to remove all lubricants, loose dirt, and firing residues. Remove all grease and oil from the locking and camming surfaces on the bottom of the barrel. Although the outside of barrel may be wiped with a solvent-moistened patch if desired, it’s not usually necessary. Thoroughly wiping off the old lubricant is normally all that’s required. For removing old, dirty lubricant I prefer to use 91 or 99 percent isopropyl alcohol (see below), but use it on metal parts only, not plastic or the sights.

b. Moisten a cleaning patch with solvent and swab out the bore. Change the patch, moisten with a copious amount of solvent and swab the bore again, this time leaving the solvent to soak while you clean the rest of the pistol. (If the gun hasn’t been cleaned for some time, brushing the bore five or six times before applying solvent is a good idea.)

c. Once the rest of the gun is clean, go back to the barrel and finish cleaning the bore. After the bore has been moistened with solvent and allowed to soak for a time, it should be swabbed dry with a clean patch. At this point it is usually necessary to brush the bore to loosen the powder residues, even if the bullet jacket (copper) fouling has been removed. Brush the interior of the barrel (the bore) by passing the bronze cleaning brush back and forth through the barrel 10 times (each way). More brushing may be necessary if the bore is very dirty, but 10 times is a good starting number. If a combination cleaner/lubricant like Break Free is used, it may be used on the brush while brushing the bore. Other solvents, especially if they are designated as “copper removing,” may attack the brush itself and therefore should not be used directly on copper/bronze brushes. Nylon bore brushes are available and may be used with aggressive solvents if desired.

Note: Do not use stainless steel brushes for cleaning any part of the gun.* Stainless steel may scratch the bore (resulting in a barrel that becomes dirty more easily and is harder to clean) and remove the protective finish from other parts. Do not pull the brush back through the barrel until it has been pushed all the way through. Reversing the brush inside the bore can damage the brush and the barrel. If possible, always clean the barrel from the breech (chamber end). Cleaning from the muzzle is more likely to damage the rifling in the bore and that can destroy the pistol’s accuracy. If a jag is used, be careful when pulling it back into the bore so that it does not strike the muzzle or rifling. Do not allow the cleaning rod to rub against the barrel, especially at the muzzle end.

[* Some people have reported good results with using a toothbrush-style stainless steel brush on the breech face. That area has no finish to scratch or remove, and it’s usually not highly polished, so it may not cause a problem. In any event, I still prefer a copper or brass brush for that area. They may leave a little copper or brass residue, but that’s easily wiped off.]

If necessary, the bore may be brushed again as required, but excessive brushing should be avoided; let the solvent do its work. The barrels of SIG pistols are very high quality, and a dry, clean bore will be smooth and shiny. Any visible streaks or other residue show that the bore is not completely clean. However, it may be very difficult to remove all residues by ordinary means and in fact this is not necessary; minor streaks and residues may be ignored.

3. Recoil spring and guide. These two parts usually require nothing more than wiping with a rag or paper towel. Note that the recoil spring of most SIG models has (or should have) a tight end and a loose or open end. The tight end goes on the recoil spring guide rod first; the idea is that it’s held captive on the rod when installed properly. To remove a tight-fitting recoil spring from the guide, hold the flange of the guide and twist the spring clockwise while pulling with your other hand.

Most SIG recoil springs are of a multi-stranded design which makes them less prone to breakage. If you notice that any of the strands are broken, however, replace the spring as soon as possible.

The recoil spring of SIG model P229 pistols chambered for 357 SIG and 40 S&W has a central strand surrounded by six additional strands. The central strand often moves out from the rest, but that’s normal and not a concern unless the migrating strand moves more than a quarter turn. Once it gets to that point it should be replaced.

The recoil springs of the P239, P245, and Pro-series SIG pistols are flat and don’t have a tight end.

4. Slide assembly. Carbon firing residues (soot) will accumulate inside the barrel channel of the slide, on the breech face (where the firing pin comes through), and on the bottom side of the breechblock (the part that holds the extractor and firing pin). (Only some SIG handguns have separate, removable breechblocks.)

a. Wipe all parts with a patch lightly dampened with cleaning solvent or 91-99% isopropyl alcohol. Avoid using a patch that is so wet that solvent is squeezed into the firing pin hole or other openings in the breechblock. Dirty solvent that runs into the breech block mechanism is difficult to remove and if it builds up enough, can interfere with the firing pin. Holding the slide with the muzzle end down while cleaning the breechblock will minimize solvent running inside.

b. Stubborn residues, especially on the breech face where the bottom of the cartridge case contacts it, may require scrubbing with the toothbrush, or even better, a similar brush with brass or copper bristles, followed by a cotton swab lightly moistened with cleaning solvent. A brass scraper that looks something like a screwdriver with a small brush on the other end is also available as a gun cleaning tool. The scraper is useful for removing the really tough residues found in the corners of the breech face. Scrapers can be easily made from brass (or copper) sheets or tubes (found in many hobby shops and hardware stores) or even a flattened brass cartridge case. Solvent may be used with the brush, but remember to avoid using so much that solvent gets into the breech block.

c. Small nooks and crannies in the slide assembly may be cleaned by wrapping a patch around the end of the cleaning rod, by rolling a patch up into a tight cylinder, or (best) by using cotton swabs. Again, use cleaning solvent if necessary, but only the amount that’s required. Often isopropyl alcohol works fine for this cleaning chore.

5. Frame assembly. Carbon residues, unburned grains of gunpowder, and sometimes small metal shavings from the bullet or cartridge case will accumulate at various places inside the frame, in particular around the magazine well. A long bristled brush is useful for primary removal of metal fragments and gunpowder grains and dirt and dust that gets into the gun during normal handling and carrying. Brushing or swabbing with a dry bore mop or cleaning patch before using solvent is often the most effective way to remove such debris. Carbon residues may have to be removed by using the toothbrush or patches or swabs moistened with solvent. As stated elsewhere, solvent should be used sparingly. Solvent can carry dirt into inaccessible parts of the gun and remove the grease and oil on interior parts. After cleaning, excess solvent should be wiped off the gun.

The interior of the magazine well should be wiped out with a rag or paper towel. A bore mop on the cleaning rod is also an excellent way of cleaning the magazine well. Do not use lubricants or solvents inside the magazine well unless absolutely necessary. The frames of current-production SIG handguns are made of anodized aluminum, stainless steel, or plastic so protective coatings are seldom necessary to prevent rust. The interior of the magazine well does not normally become dirty enough with firing residues to require solvents to clean it; scrubbing with a dry cloth patch or bore mop is usually sufficient. Residues from lubricants or solvents in the magazine well will hold dust and other dirt which may interfere with the insertion and removal of magazines.

6. Grip plates. The grips are screwed to the frame and do not need to be removed for routine cleaning and maintenance. The screws are made of soft steel that may be damaged by using the wrong screwdriver. When installing the screws, turn them in until they are just snug and then 1/8 to 1/4 turn more. Be careful, however, not to tighten the screws so much that the screw or frame (much worse!) is stripped.

Caution: If the grip plates are removed for any reason, care must be used to avoid dislodging and possibly losing the springs on both sides of the gun. Installing the trigger bar spring improperly (and it’s easy to do) may disable your gun.

Caution: When removing grip plates, don’t lose the star washers under the panel screws if they are present. They’re required to keep the screws tight, but more important, if they’re missing, the screws will probably extend into the magazine well and interfere with insertion and removal of magazines. The SIG models that use washers are the P220 and P225.

7. Magazines. The magazine is typically the most neglected part of the gun, but for reliable operation, it’s more important than the barrel. A dirty barrel may reduce your gun’s accuracy slightly, but a dirty or damaged magazine can turn your gun into a single shot or lock things up entirely. All of the magazines you carry should be disassembled, inspected, and cleaned every time you clean your pistol--whether they’ve been used or not.

There are two basic ways of disassembling SIG pistol magazines. Some P220 magazines have a flat, solid floor plate and the end of the magazine spring is visible on the bottom left side, just above the floor plate. While holding the magazine upside down, press the spring end down with a small screwdriver and push the floor plate forward. Most magazines have base plates with a round hole in the middle and a small plunger that protrudes into the hole. Depress the plunger with a non-marring object and push the floor plate forward and off. When disassembling any magazine, hold it so that if the spring gets away from you it doesn’t hit something important like an eyeball. As stated earlier, eye protection is always a must. Pull the spring out and then let the follower drop out of the magazine tube.

Magazines like the 10-round versions for the P226, P228, and P229 have an internal bottom “insert” that is held captive by flanges on the magazine tube when the floor plate is removed. The insert can be removed by pressing down on one side and allowing the other edge to clear the flange and be lifted out.

Firing residues (including soot, unburned powder grains, and metal shavings) will accumulate on the outside and inside of the magazine--but especially inside. Clean the magazine by brushing and swabbing with a dry bore mop or cleaning patch. Like the magazine well of the pistol, solvents and lubricants should be used very sparingly with the magazine. Residues may hold dust and dirt, and vapors or fluids from such materials may deactivate your ammunition. If solvents or lubricants must be used for complete cleaning or rust removal and prevention, all parts should be wiped as dry as possible. If a substance with a volatile carrier (like WD-40) is used, care must be taken to allow the carrier to evaporate completely before the magazine is loaded.

If you carry magazines in pouches, inspect them regularly and remove dirt and debris. Dirty magazine pouches are a prime cause of dirty magazines and dirty, contaminated ammunition. Some pouches are tight enough to hold rainwater or melted snow.

Magazines can be damaged if dropped (as during reloading drills). If the feed lips are bent or damaged, the cartridges may not feed properly. SIG magazines are fairly sturdy and will seldom be damaged during normal use, but they should nevertheless be examined closely at the end of all training sessions and any other time they’re dropped. If there is any doubt about the condition of a magazine, it should be test fired for reliability. Fixing a magazine by bending the lips is rarely successful and “repaired” magazines should never be carried for duty or defensive use. I have separate magazines for my guns that I use only for training and competition purposes. If possible, carry magazines should be inspected and tested regularly, but not subjected to deliberate abuse.


The purpose of lubrication is to reduce friction that can interfere with the proper functioning of the gun and to protect the gun from rust and corrosion. Like solvents, the only lubricants (oil or grease) that should be used on your SIG pistol are ones that are specifically designated by the manufacturer as being designed for guns. Lubricants made and marketed for other applications should be left to those applications.

Although either grease or oil may be used for all gun lubrication applications, I prefer grease whenever it’s possible to use it properly (that is, when the parts can be disassembled and the grease placed directly on the right spots; smearing it around the general area is of no value). For operator maintenance on the field-stripped pistol, I again prefer gun grease over oil. When lubricating a part, first wipe it as dry as possible and then apply the grease. Grease should be rubbed in until it loses its color; smearing it on in big globs is a waste and allows it to run (or ooze) off and get on other things. If you use oil, apply it sparingly and directly to friction points.

Lubricant, whether grease or oil, should be visible on the part and it should be possible to feel it when it’s touched. On the other hand, if the lubricant moves under the force of gravity (that is, runs off), then there’s too much of it. Lubricant that runs off is wasted and gets into and onto places where it doesn’t belong (like clothes and ammunition). However, extra lubricant may be used on the gun before it is used for an extensive training session. Not only will the extra lube help protect the gun, it may also make cleaning easier by keeping firing residues in a semi-liquid state.

Another reason to use lubricants--especially grease--sparingly is that most of them thicken and become “stiff” in cold weather and may cause malfunctions.

The general cleaning rule is to remove everything that’s not part of the gun. The lubrication rule is to lube anything that’s shiny. An addition to the shiny rule is the outside of “carbon” steel slides and anything else that’s subject to rust (like the trigger and other “controls”). The amount and type of rust protection necessary depends on your local environment and use of the gun. Regardless of what methods and products are used, the key to preventing rust is regular and frequent inspection of the gun and reapplication of rust preventative as required. In some situations, that may be every day or even more often. A silicone cloth (sold at gun and sporting goods stores) works fairly well for exterior rust prevention and doesn’t leave oily residues that can stain clothing.

Specific lubrication points in the field-stripped pistol
(remember the “shiny parts” rule):

Recoil Spring Guide:
Along the rod.

The locking and camming surfaces and lug on the bottom of the barrel. The outside of the round part of the barrel where the “smiles” form. An exception to the shiny rule: don’t put any grease inside the barrel or the chamber (where the cartridge goes) or on the feed ramp (the sloped part leading into the chamber).

It’s very important, however, that the bore be well protected against rust. A thin film of gun oil or CLP is usually all that’s required, but a heavy coat (which must be cleaned out before the gun is fired!) is recommended for long-term storage or storage in rust-promoting environments.

Any shiny spots on the rails; rails should be lubricated, but not excessively. The exception to this guidance pertains to guns with stainless steel frames and slides. Most users of SIG pistols having stainless slides and frames report significantly more friction between those parts than aluminum frame guns. I use more and heavier lubricant on “ST” model SIGs. The shiny area on top of the locking insert; that’s the steel block that fits inside the frame in front of the magazine well.

The shiny spot on the top of the disconnector. That’s the small tab that sticks up from the trigger bar on the right side of the magazine well.

The shiny patch inside the top of the slide in front of the ejection port. The shiny ridge down the middle of the breech block that rides over the hammer. Note that only the very back of this ridge contacts the hammer; the front section comes in contact with the ammunition in the magazine and should receive nothing more than a very light film of lube, if that. The barrel and recoil spring guide should already be lubed, but if you want you can put a bit of lube around inside the holes in the frame that they extend through to the front.

As noted above, the magazine should be kept clean of anything that might hold dust and dirt and could deactivate the ammunition. A very light coat of rust preventative can be put on the spring and the outside of the magazine tube can be rubbed with a silicone cloth or a very light rust preventative, like a thin film of CLP. Stainless steel magazine tubes should be left clean and dry under most conditions.

After cleaning, lubricating, and reassembling the pistol, conduct a function check. Manually cycle the slide back and forth several times to ensure that it moves freely and that the barrel and slide lock in position as they should. Dry fire the gun, both double action (with the hammer down) and single action (with the hammer cocked). Insert an empty magazine and pull the slide back to confirm that it locks open. Remove the magazine and release the slide by depressing the slide catch lever; repeat the test by pulling the slide back and releasing it by hand. Finally, remove the magazine by depressing the magazine catch (release button) to ensure that the empty magazine drops freely from the gun; repeat three or four times.

The following is the full function test that I conduct after detailing a SIG pistol. Note that I’m not recommending that it be used after every routine cleaning, but it can’t hurt. It is a good protocol to know if you’re inspecting a used gun.

This testing must be done with the gun unloaded. Unload all magazines and remove all ammunition from the area. Double check to ensure the pistol is not loaded.

1. Safety lock (slide removed from frame and barrel removed from slide; lay the slide on its sights):
a. Push in on rear of firing pin. Pin should not protrude from breech face.
b. Depress and hold the safety lock in and push in on rear of firing pin. Firing pin should protrude from breech face.
c. When you release the firing pin, watch the safety lock. It should snap back out into its normal rest position quickly and freely.

2. Assemble the pistol. Manually cycle the slide to ensure it moves smoothly and normally.

3. Decocking lever:
a. With the hammer cocked, put moderate pressure on the hammer spur to ensure it remains cocked.
b. Decock the hammer with the decocking lever.
c. Ensure that the hammer comes to rest in the safety intercept notch and cannot contact the firing pin when pushed forward manually.

4. Double action function:
a. With the hammer decocked, pull the trigger and ensure the trigger functions normally.
b. Ensure that the hammer moves normally and drops forcefully to strike the firing pin (use a nylon plug or pencil to check firing pin movement). Note that any object used to check the firing pin function will be expelled from the barrel forcefully; observe all safety precautions. Don’t look down the barrel!

5. Disconnector function:
a. With the hammer down and the trigger pulled and retained to the rear, pull the slide to rear and release, cocking the hammer.
b. With the trigger held to the rear in the pulled position, ensure that the hammer remains cocked.
c. Allow the trigger to move forward and ensure it resets.
d. Pull and hold the slide to the rear far enough to drop barrel out of battery; pull the trigger to ensure the disconnector functions properly (the hammer should not fall).

6. Single action function:
a. After checking the disconnector, allow the slide to go into battery, then allow the trigger to move forward and ensure it resets.
b. Pull the trigger; check firing pin function with nylon plug in the barrel.
c. After releasing the trigger, ensure that the hammer is pulled back to the reset position by the hammer reset spring and cannot be pushed forward to contact the firing pin.
Note that if you have an older P220 without a hammer reset spring, the hammer will remain forward after dry firing or if the hammer is lowered by “thumbing” it down.

7. Magazine and magazine catch function (check each one):
a. Check magazine catch for free movement in and out.
b. Check for smooth, normal movement of magazine follower.
c. Insert magazine and ensure it locks into place with slide forward.
d. Release the magazine by pressing the magazine catch and ensure it drops freely.

8. Loading and cycling function: a. With three dummy rounds loaded into the magazine (check each magazine) and the slide forward, insert the magazine and ensure it locks in place.
b. Chamber a dummy round by pulling the slide to the rear and releasing it; ensure the slide moves smartly and the round chambers properly.
c. Pull the trigger and with trigger held to rear, manually cycle slide; do this as fast and forcefully as possible to mimic the firing cycle. Ensure the next round is chambered properly. Repeat for all rounds in magazine. Note that this manual loading test is not as valid as test-firing the gun, but be suspicious if problems occur.
d. After the last round is ejected, ensure the slide locks to the rear. Check to ensure that the slide catch lever moves to the top of the arrestor (intercept) notch.
e. Drop the magazine and ensure it falls freely from the gun.
f. Release the slide by depressing the slide catch lever.

Miscellaneous Observations:

I’ve tried many different cleaning solvents:

Break Free CLP isn’t a particularly good bore cleaner, but it won’t hurt anything, either. It can be applied directly to brass/bronze bore brushes to enhance the cleaning process. There are other Break Free products besides the CLP and I suspect they are better cleaners, but I don’t have any personal experience with them.

Hoppe’s “number 9 powder solvent” perhaps works a little better as a bore cleaner than Break Free CLP, but not much. It is an old formula that was developed for removing the highly-corrosive black powder and early priming residues of 100 years ago. It is somewhat effective as a rust preventative, but it makes more sense to use a modern dedicated product like CLP or another gun oil.

Note: Do not use the following method for chrome-lined barrels.

The one thing I do use Hoppe’s for is to immersion soak a dirty barrel that doesn’t want to come clean without a lot of effort. I stand the barrel up in a container full of Hoppe’s and let it soak for 24-72 hours (or longer, if desired) and then most fouling will brush out easily. I’ve found the ideal soaking container to be an 8-oz., wide-mouth “Nalgene” bottle. It’s just large enough to hold a 4.5″ SIG barrel, is unbreakable and resistant to the Hoppe’s, and has a tight-fitting screw lid to prevent spills, prevent evaporation of any volatile components, and to keep the smell in. It may be possible to use other solvents for long term immersion soaking, but use caution when choosing them. Some solvents have a reputation for attacking steel after long exposure and others are water-based. You’d no more want to leave your barrel in them for hours at a time than you would leave your barrel in the kitchen sink. Hoppe’s is mild stuff but works well for long-term immersion soaking.

Remember: Do not use the above immersion soaking method with hoppe’s # 9 for chrome-lined barrels.

Shooters’ Choice is a satisfactory general purpose cleaner; it does a decent job on powder residues and it will remove copper jacket fouling if it’s allowed to work for a significant amount of time. Applying it to a bore brush will enhance its effectiveness, but it also attacks brass/bronze brushes so they should be rinsed in hot water and detergent immediately after use.

Butch’s Bore Shine is a more aggressive copper removing solvent than Shooter’s Choice and is what I use most of the time for that purpose. I’ve left it in pistol barrels as long as overnight with no apparent problems. I don’t apply it to bore brushes and I don’t expect it to remove powder residues.

Sweet’s 7.62 Solvent contains a high percentage of ammonia and is the most aggressive commercial copper-removing solvent that I’m familiar with. I don’t leave it in a bore for more than 15 minutes at a time. I use it when nothing else seems to be working. Its high ammonia content makes it capable of causing severe eye damage, so be sure to wear eye protection when using it. In fact, of course, eye protection should be used whenever you field strip a gun or use any type of solvent or cleaner.

Isopropyl alcohol. I’ve found 99% isopropyl alcohol (available at drug stores) to be an inexpensive, effective degreaser and solvent for removing soot-type firing residues. Some lubricants work better if applied to a thoroughly-degreased metal surface and 91 or 99% alcohol works well for the purpose. Another advantage of alcohol as a cleaner is that it evaporates without leaving any residue, and if it runs inside inaccessible places like the firing pin channel or breechblock, it’s less likely to cause problems. Isopropyl alcohol is of course flammable and care must be exercised when using it; I use a small, 2 ounce “working bottle” of the stuff to minimize the dangers of spilling it. Because it is a thorough degreaser, steel parts must be protected with oil or other rust preventative after using it. Finally, I haven’t experienced it myself, but it’s said that alcohol can damage plastic parts like grip plates and polymer frames. It’s best, therefore, to keep it away from them as well as sights, especially night sights.

MPro-7. Although I’ve never been able to confirm it, this product seems to be a water-based detergent cleaner with gun-friendly additives. It does work well on plastic parts. I use it to clean the sooty firing residues that accumulate on the dust cover (front of the frame) of plastic pistol frames. I spray it on, let it sit for a few minutes (it’s probably best not to overdo the time), and wipe off. The gelled form works very well for cleaning plastic magazine followers; again, apply, sit, wipe. One caution: I once allowed the gelled version to remain in contact with a nickel plated hammer for a couple of days and a brown rust-like stain developed that required significant effort to remove. As with any product, it’s best to follow the manufacturer’s instructions.

I sometimes use Kroil, a penetrating oil, for removing powder residues. It has to be used with a bore brush for normal cleaning. Some people use it for prolonged soaking or immersion, but in my experiments it doesn’t work as well as Hoppe’s number 9.

After 500-1000 rounds I sometimes use a more thorough cleaning procedure than patches and a brush. I remove the obvious copper fouling with a chemical solvent (Butch’s or Sweet’s) and then go after the powder fouling with a mild abrasive. I use a felt pellet along with J-B Bore Bright (not the original J-B “bore cleaner” which is more abrasive) and Kroil. Be certain to completely remove all of the Bore Bright before firing the gun. (I use this method only if the bore isn’t thoroughly cleaned by other methods, such as immersion soaking.)

Kroil, Bore Bright, and the felt cleaning pellet system are available from Brownells.

There are other good cleaning solvents on the market. Just be sure to pay attention to what they’re intended to accomplish; the copper-removing solvents I’m familiar with aren’t particularly good for removing powder residues.

My favorite lubricant for carry or duty pistols is TW-25B at the moment, but I have used Wilson Ultima-Lube grease with good results. SIG used to supply a sample of TW-25B with their pistols, but has evidently discontinued that practice. For carry/duty use, though, I’m perfectly satisfied with the product. Applied properly, it works well in both very hot and very cold temperatures. The liquid carrier will evaporate in time, changing the appearance of the lube on working surfaces, but I tested a P220 that had been lubed for duty purposes with TW-25B nine months before and the gun still functioned normally. With any defensive gun, though, lube should be replaced more frequently as a matter of course; SIG Sauer recommends doing it monthly.

I also use Break Free CLP or Mil-Comm MC2500 oil if I must lubricate something that I can’t disassemble and apply grease directly and properly to the parts.

I use RIG “+P Stainless Steel” grease on the friction points between the stainless steel frame and slide of guns like the P226ST. RIG grease is also recommended if the gun will be fired extensively, as during a range session. My SIGs that I use only at the range are heavily lubricated with +P RIG or “Slide Glide” (see next).

During warm weather, I also use Brian Enos’ “Slide Glide” for range work. High-viscosity greases help prevent what Bruce Gray refers to as pistols’ “battering themselves to death.” Slide Glide has been implicated in causing slow slide velocity malfunctions in cold temperatures, so use it in accordance with the manufacturer’s instructions and recommendations. Link:

Mention and discussion of specific cleaning and lubricating products are not intended to suggest that others aren’t as good or even better; I just haven’t tried them. The ones I use work as described and that’s why I use them.

SIG Sauer’s recommended maintenance and parts replacement schedule
(as of March 2008):

Barrel: If the pistol exhibits keyholing or unacceptable accuracy.
Decocking lever spring: 10,000
Extractor: 20,000
Extractor spring: 20,000
Firing pin: 20,000
Firing pin spring: 20,000
Magazine spring: When magazine fails to lock the slide open. *
Recoil spring: 5,000 †
Safety lock spring: 20,000
Slide catch lever spring: 10,000
Takedown lever: 20,000
Trigger bar spring: 10,000

Mainspring (hammer spring): 5000 or when misfires due to light hammer strikes occur and other causes have been eliminated. Note that this is my own recommendation; SIG Sauer makes no recommendation about the mainspring in the armorer manual. I was told by a fellow armorer, however, that when he asked about it SIG’s informal guidance was that a mainspring should last 40,000 rounds.

* I also recommend replacing the magazine spring when ammunition is not held securely. This can occur before slide lock failures.

† I had seen an early recommendation here that the recoil spring be replaced after 3000 rounds, and that’s what I follow.

SIG considers the extractor used in P220 stainless steel slides to be a “sacrificial” part, and that it should be replaced after it’s removed from the slide.

This is the service schedule that was provided along with the above parts schedule:

Operator - Clean and Lubricate: After every firing or exposure to water chemicals, dirt, or other contaminants.
Operator - Clean and Lubricate: Annually during storage.
Operator - Clean and Lubricate: Monthly when carried as duty weapon.
Operator - Function Check: Whenever disassembled and reassembled.
Armorer - Field strip and inspect for proper maintenance: Annually.
Armorer - Detailed disassembly and inspection: Every three years or 5000 rounds fired.

The detailed disassembly does not necessarily include spring replacements.