Sig P220 Serial Number Dating

Often, in firearms-related forums and social media groups like the SIG Sauer Legion Facebook group, I'll see the terms 'West German SIG' and 'German SIG' used interchangeably. I'll also see guns referred to as 'German-made' when that might not actually be the case. Some owners mistakenly (but innocently) assume that a P-Series SIG Sauer with 'Made in Germany' stamped on the slide, or a frame engraved 'Frame Made in Germany' is no different than a pistol with 'Made in W. Germany' stamped on the slide — when that's actually not the case.

Sig recommends and trains so that the system is to be used as DAO (Double Action Only). You will see that they only list the 6.5 lbs. Trigger pull in DA on their DAK models specifications sheets. They recommend that users should be trained to fire the pistol by utilizing the full double action trigger stroke so that the trigger is a consistent. Often (but not always) on West German SIGs, an Eagle-N proof mark will also appear on the frame, following the serial number, like this: Nitro proof mark on a West German P220 frame A true West German SIG will always have proof marks and a date code. Thus, it's impossible to load each bb by serial number reference. Sig sauer da/sa pistols chambered in the holster for related topics. Thus, sig p226 elite scorpion tb was excellentsomething you haven't dated your freedom sig sauer guns with a few months now. So as a sig p220 carry a single-action. Sig P228 Serial Number Lookup. By weiflorkedogg1986 Follow Public. Germany on the right-hand side of the slide, so its appropriate to call it a West German SIG. Ill also see guns referred to as German-made when that might not actually be the case. Some owners mistakenly (but innocently) assume that a P-Series SIG Sauer with Made in Germany.

There are a number of differences between SIGs made in Germany (or West Germany) vs. those made with parts made in Germany and assembled in the US. Those differences depend upon which models we're taking about. For a discussion on differences on the P226 model, for example, check out my P226 Version History and Head-to-Head Comparison video. As to whether or not those differences make one version better than the other is a matter of debate… better left to discussion forums and Facebook groups. There's no denying, however, that SIG fans generally tend to find 'true' German and particularly West German SIGs somewhat more collectible and desirable, and so a brief overview of how to distinguish different SIGs based on their actual provenances might be useful.

'Made in W. Germany' SIGs

Switzerland may have great cheese, chocolate, and pocket knives, but their strict laws severely limit the ability of Swiss companies to export firearms. So Swiss companies wishing to sell their products outside of Switzerland can work around this restriction by partnering with a non-Swiss company. So in the early 1970s, SIG (which takes its letters from Schweizerische Industriegesellschaft — meaning 'Swiss Industrial Company') partnered with a West Germany-based Sauer & Sohn, who was known for their quality hunting rifles, and the SIG Sauer partnership was born. Their first joint project was the SIG P220, which launched in 1975. Prior to their partnership with Sauer, SIG had previously produced the SIG P210 for the Swiss Army, so the two companies built upon the principles of the SIG P210 for the SIG P220, which they planned to export.

Sig P220 Serial Number Lookup

Because Sauer & Sohn's manufacturing facility was located in Eckernförde, West Germany, all firearms produced at this facility received a 'MADE IN W. GERMANY' stamp on their slide:

Early West German SIG P220 with 'Made in W. Germany' stamped on the slide

The above model also happened to be imported to the US by SIGARMS INC. in Tysons Corner, VA, the original 1985 location of SIG Sauer's US operations — which then consisted only of importing and selling the West German-made guns.

In most cases, the 'MADE IN W. GERMANY' stamp appears in uppercase, but there are also examples of the stamp appearing in title case, as with this 1988 SIG P226:

1988 SIG P226 with 'Made In W. Germany' stamped on the slide

Ccleaner download. This brings us to the most important rule for determining a West German SIG: if it doesn't have 'MADE IN W. GERMANY' (or 'Made In W. Germany') stamped on the slide, it's something other than an 'outright' West German gun. If it merely says 'MADE IN GERMANY,' it's not a West German SIG, and it's incorrect to refer to it as such.

Origin of the phrase 'Made in Germany'

This is a good place to take a quick pause and explain the origin of the phrase 'Made in Germany,' because it's probably not what you think, and you might not even believe it.

In 1879, Otto von Bismarck, first Chancellor of Germany, raised import tariffs on all foreign goods entering Germany in an effort to protect German manufacturers by keeping the prices of their goods lower when compared to foreign goods (Governments still do this kind of things today). With this protection, the German manufacturing sector grew rapidly, and German merchants began increasing their exports across the markets of Europe. Because British-made goods were considered the highest quality at the time, German merchants routinely marked and packaged their goods falsely — attempting to pass them off as British-made.

In response, Britain passed the Merchandise Marks Act of 1887, which forced foreign manufacturers to mark the true country of origin on their exported good (and gave Britain the power to enforce it). Other countries had also been falsely marking their products, but the Germans had been the worst offenders by far, and this Act was aimed squarely at them. The British forced German merchants to place 'Made in Germany' on all goods they produced, thereby protecting the integrity of British goods while simultaneously allowing consumers to know when they were purchasing goods from protectionist governments like Germany.

This means that it was Britain that actually coined the term 'Made in Germany,' and forced German merchants to use it to prevent counterfeiting.

As time went on, German-made goods eventually built their own global reputation for quality and reliability, so that now the phrase 'Made in Germany' is a mark of excellence, even though the phrase is not trademarked or controlled by any central regulatory agency.

The term 'Made in Germany' was still widely used even on West German goods from 1945 until 1973, when the West German Federal Court (Bundesgerichtshof) made a ruling that the phrase 'Made in Germany' doesn't allow consumers to properly distinguish between the two Germanys of the time, and so 'Made in West Germany' (as well as 'Made in GDR') started to appear instead. As for how and when it transitioned back to 'Made in Germany,' particularly in the case of SIG Sauer pistols, you'll have to continue reading to find out!

Proof Marks and Date Codes

Another way to identify a West German SIG is the existence of proof marks and date codes, though their existence alone does not automatically determine a pistol's provenance. Even if German proof marks and date codes do appear on the gun, it's still not correct to refer to it as an outright West German SIG if it's missing the 'MADE IN W. GERMANY' on the slide.

A full discussion of SIG Sauer Proof marks and date codes deserves its own article, so I went ahead and wrote one. You can take a break from this article and read it now, or check it out when you're finished with this one. It explains the origin of proof marks, what 'proofing' is and why it's important… and also dispels a few of the Internet myths surrounding SIG proof marks in particular.

But the TL;DR version of that article is that proof marks indicate where and how a firearm was test fired and declared safe for use, and all bonafide West German SIGs will have one proof mark showing where it was tested, another proof mark showing what type of test it passed, and a two-letter date code stamped on the 'chin' of the slide, as on this 1989 SIG P226:

Proof marks and date code on a 1989 West German SIG P226

Depending on the gun model and vintage, it's also possible to see the order of the proof marks swapped, like on this 1977 SIG P220:

German gun manufacturers used the following letters to indicate proofing dates:

SIG opted to not use the letter 'I' because it looked too much like the numeral '1,' so it used J = 8. Other German manufacturers (like Walther and H&K) were fine using I = 8, but avoided using J altogether.

So the first example tells us the gun was proofed in the city of Kiel (17 miles from SIG's manufacturing facility in Eckernförde), and that it successfully passed testing with 'Nitro' rounds in 1989. The second example tells us that gun passed the same test in Kiel's proofing facility in 1977.

Often (but not always) on West German SIGs, an Eagle-N proof mark will also appear on the frame, following the serial number, like this:

Nitro proof mark on a West German P220 frame

A true West German SIG will always have proof marks and a date code. The only exception I can think of to that rule is the 1977-1980 Browning BDA, which was the first version of the P220 imported into the US as a rebranded Browning. It said 'SIG-Sauer System Made in W. Germany' on the right-hand side of the slide, so it's appropriate to call it a West German SIG:

'Made in W. Germany' marking on a Browning BDA / SIG P220

But because the gun was imported only for the US market as a Browning firearm, and not a SIG Sauer, it didn't require proofing to be legal to sell, so that's why you don't see any German proof marks on the slide chin. As far as I know, this is the only exception where a gun that can be considered a 'West German SIG' is lacking proof marks. If you know of another, please let me know in the comments!

For a more in-depth understanding of proofing and proof marks, including exactly what the squished-bug looking proof mark is actually supposed to represent, check out my article on SIG proof marks.

Post-Reunification 'Made in W. Germany' SIGs

Quick history refresher: The country of West Germany (officially theFederal Republic of Germany) was founded following World War II on May 23, 1949. The SIG Sauer partnership produced its first firearm, the P220, in West Germany in 1975, and continued to produce and export firearms designated as 'West German' products for 25 more years, until East and West Germany were reunified on October 3, 1990 and commonly referred to as 'Germany' once again… though technically the combined country's official name remains to this day the 'Federal Republic of Germany,' and the 'German Democratic Republic' (aka East Germany) was essentially absorbed by West Germany.

So you might imagine that because 'West' Germany no longer existed after October 1990, that any SIG Sauer pistols proofed after that date could not be called West German SIGs… but you'd be wrong.

SIG pistols stamped 'Made in W. Germany' with date codes from 91, 92, 93, 94, and even 95 exist. But how?

The apocryphal story goes that SIG Sauer had a 5 year stockpile of slides already manufactured and stamped 'Made in W. Germany,' and that it simply took them five years to use them all up before they had to make more, at which point they started stamping 'Made in Germany' on them. That urban legend is untrue, and would indicate extremely poor inventory management on the part of SIG Sauer… especially when you consider that it would mean they'd have to stockpile 5 years of slides for their entire lineup of pistol models.

The reality is much more believable. As part of the 1990 Reunification Treaty negotiations, West German manufacturers expressed major concerns about diluting their reputation for 'West German quality' as a result of the flailing former East German economy and manufacturing sector (famous for bringing you such manufacturing missteps as the Trabant) combining with theirs under a common market and currency. So when the 1990 Reunification Treaty was ratified, the German government allowed West German manufacturers to continue referring to their products as 'West German-made' for a 5 year transition period. That made it legal for SIG Sauer to continue producing and exporting products marked 'Made in W. Germany' through October 3, 1995 — which is exactly what they did. That's why it's possible to find SIG Sauer pistols marked 'Made in W. Germany' with date codes up to KF, or 1995… even though some of those guns were, technically, manufactured, assembled, and proofed in post-reunification 'Germany.' Still, if it's stamped 'Made in W. Germany' and has German proof marks and date codes, it's appropriate to refer to such a pistol as a West German SIG.

Perhaps not coincidentally, 1990 was the same year that Sigarms Inc. (the American branch of SIG that had been set up in 1985 to import West German SIGs to the US market) moved to Exeter, New Hampshire to set up a new manufacturing facility. By 1992, the first fully American-made SIG pistol, the SIG P229 in .40 S&W, was being produced in Exeter.

'Made In Germany' vs. 'Made In Germany / Assembled In US' SIGs

Even though we've busted the myth that SIG's stockpile of slides was 5 years deep, and I'm certain they tried their best to forecast parts inventory approaching the cutoff of the 5 year post-reunification transition period, it's a certainty they had at least some amount of slides already manufactured with 'MADE IN W. GERMANY' stamped in the slide. It's also almost certain that SIG even had some amount of assembled and proofed 'Made in W. Germany' pistols in their inventory. But selling goods marked 'Made in W. Germany' past October 3, 1995 would be illegal, so what to do?

You do the same thing you'd do with a bad tattoo: you put something else over it. SIG's solution was to stamp something on top of the 'W.' Since striking a stamp into metal is called 'peening,' this is referred among SIG owners as a 'peened' or 'peened over' slide.

There were two different versions of SIG's peening, but how and why each was applied is still somewhat of a mystery. The following information is based on photos of three different SIG P220 pistols provided for this article by the F. Leone Collection:

• G 253 XXX – which bears German proof marks with a KF (1995) date code
• G 254 XXX – no proof marks or date code
• G 257 XXX – no proof marks or date code

The earliest version is the 'swirl,' which appears on both G 235 XXX and G 254 XXX:

The second type of peen mark is an image of the Sauer 'triskelion' logo, as seen on G 257 xxx:

P220 with Sauer triskelion logo peen mark

Here's a larger view of Sauer's triskelion logo taken from the Sauer.de webpage:

Also note that P220 G 253 XXX is proofed:

Proofed P220 with a G 253 XXX serial number

While P220 G 254 XXX is not proofed, and uses a noticeably different serial number font than the proofed P220:

So to sum up, these three peened over SIG P220s with relatively close serial numbers stack up like this:

• G 253 XXX – swirl peen – proof marks – KF date – font style A
• G 254 XXX – swirl peen – no proof marks – font style B
• G 257 XXX – triskelion peen – no proof marks – font style B

So my current hypothesis is that the facility in Germany stamped BOTH types of peen marks, but that they decided to switch peen mark styles somewhere between G 254 XXX and G 257 XXX (maybe because they didn't like the swirl). I also believe that SN font style A was applied in Germany during assembly and font style B was applied in the US during assembly. That would mean:

• G 253 XXX was swirl peened, proofed, and serial numbered in Germany
• G 254 XXX was assembled and serial numbered in the US using a German-made slide that had been swirl peened in Germany
• G 257 XXX was assembled and serial numbered in the US using a German-made slide that had been triskelion peened in Germany

From the above info, we know that the 1995 SIG P220 was assembled and proofed in Germany. By 1996, Sigarms' manufacturing facility in Exeter, New Hampshire had been up and running for at least 4 years, so they assembled the two later P220s using German-supplied parts.

A SIG pistol that doesn't have proof marks, regardless of what's stamped on the side of the slide, was not assembled or proofed in Germany (or West Germany). So while it's technically proper to refer to the latter two examples as 'Made in Germany' SIGs (since, thanks to the peen marks, that's what now appears on their slides), because they lack proof marks like their barely older sister, they certainly shouldn't be referred to as 'West German' SIGs. To be extremely precise, one might refer to them as 'Made in Germany / Assembled in US' SIGs.

However… whether or not G 253 XXX should be referred to as a 'West German SIG' is a matter of debate, with very good arguments on both sides. Because it was manufactured, assembled, and proofed in Germany — by the same people on the same equipment as slightly older (perhaps only a few days or weeks older) pistols — one might argue that the only difference is the peen mark. There's no doubt that such a pistol would be identical in every other way to any other post-reunification 'West German' SIG… but the line has to be drawn somewhere, and perhaps that peen mark is the line. Or perhaps the proof marks are the line, and any SIG that had 'Made In W. Germany' on the slide, even if it the 'W' was peened over, that was proofed in Kiel should rightfully be referred to as a 'West German' SIG. If you've got an opinion, please share it in the comments.

Throughout the late 90s and into the 2000s, Sigarms' New Hampshire operation expanded, and they assumed more assembly and manufacturing tasks. Any SIG pistol with a slide marked 'Made in Germany' bearing German proof marks can be referred to as a 'true' Made in Germany SIG. Pistols with slides marked 'Made In Germany,' but without German proof marks, are built with the same components as their German sisters, but because they were assembled in the US, and therefore not proofed, I refer to them as 'Made in Germany / Assembled in US' SIGs.

Here's a example of a 'Made in Germany / Assembled in US' SIG P228:

P228 with German-made slide and frame… but assembled in the US.

Compare it to a true 'Made in Germany' P228 with German proof marks:

Hybrid SIGs

Sometimes, one might see 'Made in Germany' on a SIG's frame and assume that applies to all the firearm's parts, but that's almost never the case. As the 2000s continued on and SIG developed additional models, Sigarms in New Hampshire took on even more assembly manufacturing tasks. This led to what I refer to as 'hybrid SIGs,' where a German-made frame was shipped to New Hampshire and assembled in the US using a US-made slide and barrel, like this P220 ST:

US-made P220 ST with German-made frame

If the frame says 'FRAME MADE IN GERMANY,' but there's no mention of Germany on the slide and no German proof marks anywhere, that's pretty much a guarantee that the slide, barrel, and everything else on the gun was American-made and that it was assembled in New Hampshire. This 'hybrid SIG' is far more American than German, and so it should never be referred to as a 'German-made' gun.

The distinctions between all these variants might seem minor, but it's important to know what you're looking at, so you don't get fooled by an auction listing like the one where I found this photo of a .40 S&W P229:

US-assembled SIG P229 with US slide, US barrel, and German frame.

The frame says 'FRAME P229 MADE IN GERMANY' but there are no other German markings on the gun, which makes it incorrect to refer to this as a 'German-made' gun. But the auction listing for this gun was titled 'SIG Sauer Sig/Sauer P229 40 Cal made in germany.' Proper noun capitalization aside, that title is highly misleading, as is the description, which reads: 'this beauty is a sig/sauer model P229 in 40 cal with two 12rd mags in it's original box.it's in excellent condition and this one was made in Germany and is marked on frame.'

I can't say whether the seller was intentionally trying to mislead potential buyers, or whether he simply didn't know any better. But you should be an informed buyer, and know that if a gun is marked 'Frame Made In Germany,' and 'Germany' doesn't appear anywhere else, it's not a German made SIG. It's a US-made SIG with a German-made frame. And even if both the frame and slide say 'Made In Germany,' if it lacks German proof marks, it was assembled in the US.

Sig Sauer P229 Serial Number Date

That's not to say that there's anything wrong with this example of a P229, or with any 'hybrid' SIG. But a potential purchaser who is new to SIGs might believe this really is a 'German-made' SIG and feel justified in paying a premium for it, then feel ripped off if and when they discover the truth.

All American SIGs

As you can probably predict from the trends noted in this article, as time went on, SIG manufactured and assembled more and more firearms in the US. In 2007, US-based Sigarms was renamed SIG SAUER. By 2014, all but a few of SIG's guns were being manufactured completely in the US, including previous 'hybrid' models whose frames had been made in Germany. In 2014, SIG SAUER's CEO was quoted that his goal was to have production for all SIGs moved to New Hampshire by 2015. 'Made in Germany' will no longer appear on any part of any SIGs.

Also in 2014, SIG's German manufacturing facility surprised many by releasing a small batch of true 'Made in Germany' SIG P220 pistols, with the classic folded carbon slide and pinned breech block — but with modern German proof marks on the slide and barrel:

Surprisingly, these guns were imported by PW Arms in Redmond, Washington… and not SIG SAUER in Exeter, New Hampshire. The barrel showed a proof date of BC, meaning they'd been proofed in 2012:

SIG P220 proofed barrel with a BC (2012) date code

Nobody knows whether these parts had been in storage in Germany for more than a decade and finally assembled and proofed, or whether the German gunmakers fired up the old equipment in 2012 for a last hurrah before all manufacturing moved to the US once and for all. Either way, a few lucky buyers got their hands on a modern example of a classic German SIG that was manufactured, assembled, and proofed in Germany… and fully deserving of its 'Made in Germany' stamping.

Final Thoughts

My goal for this article was to give you enough information to easily distinguish between the following variants of SIG firearms:

1. True 'Made In W. Germany' SIGs from both the pre- and post-reunification eras.
2. True 'Made In Germany' SIGs that are manufactured, assembled, and proofed in Germany.
3. 'Made In Germany / Assembled In US' SIGs with German-made slides and frames, assembled in the US.
4. 'Hybrid' SIGs with 'Frame Made In Germany' etched on the frame combined with US-made slides, assembled in the US.
5. 'All American' SIGs made 100% in the US.

As for whether any of these variant are more desirable, more valuable, or different enough from any other to make any difference to you is completely up to you. A 'Made in W. Germany' P226 made one week before reunification is not going to be noticeably different from a P226 made one week after reunification. And a 'Made in Germany' P220 made a month or two after the October 1995 'can't say W. Germany anymore' deadline would have been made by the same people, in the same facility, using the same equipment and materials, and proofed at the same proof house in Kiel as a 'Made in W. Germany' P220 proofed one day before the deadline.

My primary goal was to help clear up some of the considerable confusion between what's a true 'Made in West Germany' SIG vs. a 'Made in Germany' SIG vs. a 'Parts Made in Germany (wink wink)' SIG, and to have a convenient place to politely link when someone wants (or needs) to know the difference. If you encounter someone who refers to them incorrectly, please be kind in how you correct them, and politely share this link.

If you have questions, comments, corrections, or other feedback, please share them in the comments below!

If you've heard someone mention proof marks or date codes when discussing a SIG Sauer pistol, but weren't quite sure what those were, then the goal of this article is to bring you up to speed. And even if you're already familiar with proof marks, maybe this article can broaden your knowledge and teach you something new.

What are Proof Marks?

Proof marks are stamps embedded in certain parts of a firearm following (and sometimes during, depending on the firearm type) its manufacturing to indicate that the firearm has been 'proven' to be able to handle the specific type of ammunition for which it was designed. In modern years, they truly do serve that purpose. But like many government regulations, their origins have more to do with self-interest than safety.

The first proof marks started appearing in 15th century France, and by the 17th century, European firearms guildsmen were heavily promoting their use — and lobbying their governments for laws requiring them — primarily to dissuade competition from non-guildsmen and scare potential purchasers away from un-proofed guns.

In 1637, after heavy lobbying from the London Gunmakers Company, a London-area firearms guild, King Charles I issued a Royal Charter setting firearms safety standards. The London Gunmakers Company set up a 'proof house' in London, and not surprisingly… firearms makers who were not part of a guild tended to fail testing more often than the guild members. Guns that passed testing were stamped with a mark representing the proof house. Over the next few decades, other countries established their own safety standards and proof houses, along with their own unique marks. Much like reciprocity of modern concealed carry permits between states, some European countries began to recognize each others' proof marks as a high enough testing standard for foreign countries' firearms to be legally imported.

Fast forward to 1914, when a number of European countries formed the CIP (Commission Internationale Permanente pour l'Epreuve des Armes à Feu Portatives) as a formal standards group to ensure consistent testing among member countries. As of 2015, the CIP includes 14 member states. In order for a civilian firearm produced in a CIP member state to be legally imported to another CIP country, it must bear the proof mark of a CIP member state (military testing standards are, predictably, different than civilian ones). The United States does not participate in CIP, but instead formed its own standards group named SAAMI (Sporting Arms and Ammunition Manufacturers' Institute). While the CIP and SAAMI do share information and cooperate, neither has a requirement regarding selling in each other's countries. Because the US is not a CIP member state, foreign guns do not need a CIP proof mark to be sold in the US, nor do US guns need a US proof mark to be sold in CIP member countries. This is an important fact that will become relevant again later in this article.

Examples of German Proof Marks

Here's an assortment of mid 20th century proof marks used through Germany's (and West Germany's) history:

The top row (a) indicates the German (or East/West German, depending on the year) city in which the proof house is located. The column marked (b) shows varios German/West German proof marks after 1945, while the column marked (c) shows German proof marks used from 1939-1945.

Here's another image showing the marks of German/West German proof houses, along with the approximate year they were first in use:

Proof Marks on SIG Sauer Pistols

Depending on it's vintage and model, you might see proof marks on a German / West German SIG's frame:

Proof mark on a West German P220 frame

Proof marks on the slide chin of a West German SIG Sauer pistol

Kiel Proof House Mark

The top proof mark indicates the Kiel Proof House. Since Kiel is only 17 miles from SIG Sauer's manufacturing facility in Eckernförde, that's the proof mark you should expect to see on a proofed SIG Sauer. Many refer to the Kiel mark as a 'squashed bug,' while others have claimed it's an oak leaf. Actually, the proof mark is based on the city of Kiel's coat of arms:

Coat of arms of Schaumburg

All true German and West German SIGs were test fired at the Kiel proof house, so the Nesselblatt proof mark is an indicator of a true German or West German SIG. I've also heard one report of the Ulm proof house's stag antler mark appearing on a the frame and slide of a 1993 SIG P226 (in addition to the Kiel mark on the slide), which would imply that the firearm required repair and re-proofing… and presumably the repair took place at a location that was closer to Ulm than Kiel. Normally, you'd expect to see the Ulm proof mark on a Walther or H&K firearm.

The German Definitive Mark and Nitro Testing

Underneath the Kiel Nesselblatt (though the order of the marks is not important), we find the image of an eagle with the letter 'N' underneath. Some incorrectly believe that the eagle mark is a remnant of Nazi-era Germany, particularly since Germany's firearms proof mark was a previously crown, and was changed to an eagle in 1939.

In actuality, the German Reichsadler (literally 'Eagle of the Realm') dates back to the eagle on the standard of the Roman Empire, and was used as a symbol of the Second German Empire as early as 1871… long before the National Socialist German Workers' Party. The same eagle design has continued its use in West Germany since 1945, but under a new name of Bundesadler, or 'Union Eagle.'

The Eagle-N mark signifies that the firearm was proofed in Germany (or West Germany, depending on when the firearm was proofed), while the 'N' indicates that the firearm was proofed using a Nitro Beschuss load. 'Beschuss' translates as 'bombardment,' 'shelling,' or 'firing' depending on context, and 'nitro' is short for 'nitrocellulose,' a highly flammable compound used to creates pressures inside the firearm higher than standard gun powder.

Sig Sauer Serial Number Date Of Manufacture

Pistols are delivered to the proof houses in their fully assembled form for proofing. For pistols, CIP standards require cartridges that generate pressure 30% higher than the standard ammunition for which the pistol is designed, so the two high pressure nitro rounds are fired through the pistol. Technicians then disassemble the pistol and examine it in a dark room using a fluoroscopic lamp, looking for magnetic flux leakage. Provided everything looks good, the pistol is re-assembled and receives the country's CIP proof mark indicating what type of test it passed (the Eagle-N or 'definitive' mark in the case of a German gun), the mark of the proof house, and marks indicating the date of the tests. The firearms is then returned to the manufacturer who can legally sell the firearm domestically or export it to another CIP country.

The 'nitro' proof mark is also referred to as the 'definitive' (or final) mark of the proof house, as opposed to a 'provisional' mark which would generally only apply to shotgun barrels in an early stage of manufacture, which are tested at proof houses to prevent the manufacturer from continuing work on defective tubes.

Date Codes

Looking back at our photo, the 'JK' under the definitive proof mark is the date code. Date codes are two-letter indicators of the year that a firearm was proofed. Major German firearms companies such as Heckler and Koch, Walther, and SIG Sauer all used a similar date code format:

German gun manufacturers used these letters in place of numbers for date codes

Using the above table, we can determine that the 'JK' date code in the photo stands for '89' — meaning this firearm was proofed in 1989… which coincidentally happened to be the year the Berlin Wall came down. This doesn't necessarily mean that the pistol was manufactured in 1989. It's quite possible the barrel was made in 1986, the frame in 1987, and the slide in 1988… but that all the parts weren't assembled together into a firearm and delivered to a proof house until 1989. Or it's possible that all the parts were actually made in 1989, and then assembled and proofed that same year. There's no way to know. A true German / West German firearm isn't technically 'born' until it's been proofed.

Note that a gun's date code is different than its serial number. It's impossible to decode a SIG serial number to determine when it was proofed, although you can try to locate the range of your SIG's serial number in this list to approximate when it was made, or call SIG Sauer with the serial number and see if they have any info in their system. Serial numbers aren't always truly representative of the chronological order of a firearm, but they can sometimes get you close. Only a date code can tell you the year of proofing.

Proofed vs. Non-Proofed 'Made in Germany' Guns

If you've read my article on West German vs. German vs. Other SIGs, you'll know that proof marks are one of the primary indicators or whether a SIG Sauer (or any other firearm) is truly 'made' in Germany (or West Germany) as opposed to assembled in the US using German-made parts… even though the parts might be stamped 'Made in Germany.' Because the US is not a CIP country, guns marked 'Made in Germany' do not need to be proofed in order to be sold here, as long as they are assembled in the US.

In my opinion, a gun without German proof marks (with very few exceptions) is not truly a German gun. Whether that actually affects the desirability or quality of the gun is for you to decide. But you should at least be aware that for most SIG purists, the existence of proof marks is what determines whether a gun is correctly referred to as 'Made in Germany.'

Putting it All Together

Now that you know how to decode proof marks and date codes, see if you can figure out where and when the following firearms were proofed. Most are SIGs, but I threw some other German guns in there just for fun. 🙂

Normally, the proof house mark is above the definitive mark on a SIG, but this is a very early SIG P220

Sig Sauer P365 Serial Number Lookup

Walther P99

Opf files. The long-term records in the file are included to protect the legal and financial rights of the government and the employee.

I welcome your corrections, questions, comments, & feedback below.

Further Reading:

Sig P220 Serial Number Dating Line

Even though we've busted the myth that SIG's stockpile of slides was 5 years deep, and I'm certain they tried their best to forecast parts inventory approaching the cutoff of the 5 year post-reunification transition period, it's a certainty they had at least some amount of slides already manufactured with 'MADE IN W. GERMANY' stamped in the slide. It's also almost certain that SIG even had some amount of assembled and proofed 'Made in W. Germany' pistols in their inventory. But selling goods marked 'Made in W. Germany' past October 3, 1995 would be illegal, so what to do?

You do the same thing you'd do with a bad tattoo: you put something else over it. SIG's solution was to stamp something on top of the 'W.' Since striking a stamp into metal is called 'peening,' this is referred among SIG owners as a 'peened' or 'peened over' slide.

There were two different versions of SIG's peening, but how and why each was applied is still somewhat of a mystery. The following information is based on photos of three different SIG P220 pistols provided for this article by the F. Leone Collection:

• G 253 XXX – which bears German proof marks with a KF (1995) date code
• G 254 XXX – no proof marks or date code
• G 257 XXX – no proof marks or date code

The earliest version is the 'swirl,' which appears on both G 235 XXX and G 254 XXX:

The second type of peen mark is an image of the Sauer 'triskelion' logo, as seen on G 257 xxx:

P220 with Sauer triskelion logo peen mark

Here's a larger view of Sauer's triskelion logo taken from the Sauer.de webpage:

Also note that P220 G 253 XXX is proofed:

Proofed P220 with a G 253 XXX serial number

While P220 G 254 XXX is not proofed, and uses a noticeably different serial number font than the proofed P220:

So to sum up, these three peened over SIG P220s with relatively close serial numbers stack up like this:

• G 253 XXX – swirl peen – proof marks – KF date – font style A
• G 254 XXX – swirl peen – no proof marks – font style B
• G 257 XXX – triskelion peen – no proof marks – font style B

So my current hypothesis is that the facility in Germany stamped BOTH types of peen marks, but that they decided to switch peen mark styles somewhere between G 254 XXX and G 257 XXX (maybe because they didn't like the swirl). I also believe that SN font style A was applied in Germany during assembly and font style B was applied in the US during assembly. That would mean:

• G 253 XXX was swirl peened, proofed, and serial numbered in Germany
• G 254 XXX was assembled and serial numbered in the US using a German-made slide that had been swirl peened in Germany
• G 257 XXX was assembled and serial numbered in the US using a German-made slide that had been triskelion peened in Germany

From the above info, we know that the 1995 SIG P220 was assembled and proofed in Germany. By 1996, Sigarms' manufacturing facility in Exeter, New Hampshire had been up and running for at least 4 years, so they assembled the two later P220s using German-supplied parts.

A SIG pistol that doesn't have proof marks, regardless of what's stamped on the side of the slide, was not assembled or proofed in Germany (or West Germany). So while it's technically proper to refer to the latter two examples as 'Made in Germany' SIGs (since, thanks to the peen marks, that's what now appears on their slides), because they lack proof marks like their barely older sister, they certainly shouldn't be referred to as 'West German' SIGs. To be extremely precise, one might refer to them as 'Made in Germany / Assembled in US' SIGs.

However… whether or not G 253 XXX should be referred to as a 'West German SIG' is a matter of debate, with very good arguments on both sides. Because it was manufactured, assembled, and proofed in Germany — by the same people on the same equipment as slightly older (perhaps only a few days or weeks older) pistols — one might argue that the only difference is the peen mark. There's no doubt that such a pistol would be identical in every other way to any other post-reunification 'West German' SIG… but the line has to be drawn somewhere, and perhaps that peen mark is the line. Or perhaps the proof marks are the line, and any SIG that had 'Made In W. Germany' on the slide, even if it the 'W' was peened over, that was proofed in Kiel should rightfully be referred to as a 'West German' SIG. If you've got an opinion, please share it in the comments.

Throughout the late 90s and into the 2000s, Sigarms' New Hampshire operation expanded, and they assumed more assembly and manufacturing tasks. Any SIG pistol with a slide marked 'Made in Germany' bearing German proof marks can be referred to as a 'true' Made in Germany SIG. Pistols with slides marked 'Made In Germany,' but without German proof marks, are built with the same components as their German sisters, but because they were assembled in the US, and therefore not proofed, I refer to them as 'Made in Germany / Assembled in US' SIGs.

Here's a example of a 'Made in Germany / Assembled in US' SIG P228:

P228 with German-made slide and frame… but assembled in the US.

Compare it to a true 'Made in Germany' P228 with German proof marks:

Hybrid SIGs

Sometimes, one might see 'Made in Germany' on a SIG's frame and assume that applies to all the firearm's parts, but that's almost never the case. As the 2000s continued on and SIG developed additional models, Sigarms in New Hampshire took on even more assembly manufacturing tasks. This led to what I refer to as 'hybrid SIGs,' where a German-made frame was shipped to New Hampshire and assembled in the US using a US-made slide and barrel, like this P220 ST:

US-made P220 ST with German-made frame

If the frame says 'FRAME MADE IN GERMANY,' but there's no mention of Germany on the slide and no German proof marks anywhere, that's pretty much a guarantee that the slide, barrel, and everything else on the gun was American-made and that it was assembled in New Hampshire. This 'hybrid SIG' is far more American than German, and so it should never be referred to as a 'German-made' gun.

The distinctions between all these variants might seem minor, but it's important to know what you're looking at, so you don't get fooled by an auction listing like the one where I found this photo of a .40 S&W P229:

US-assembled SIG P229 with US slide, US barrel, and German frame.

The frame says 'FRAME P229 MADE IN GERMANY' but there are no other German markings on the gun, which makes it incorrect to refer to this as a 'German-made' gun. But the auction listing for this gun was titled 'SIG Sauer Sig/Sauer P229 40 Cal made in germany.' Proper noun capitalization aside, that title is highly misleading, as is the description, which reads: 'this beauty is a sig/sauer model P229 in 40 cal with two 12rd mags in it's original box.it's in excellent condition and this one was made in Germany and is marked on frame.'

I can't say whether the seller was intentionally trying to mislead potential buyers, or whether he simply didn't know any better. But you should be an informed buyer, and know that if a gun is marked 'Frame Made In Germany,' and 'Germany' doesn't appear anywhere else, it's not a German made SIG. It's a US-made SIG with a German-made frame. And even if both the frame and slide say 'Made In Germany,' if it lacks German proof marks, it was assembled in the US.

Sig Sauer P229 Serial Number Date

That's not to say that there's anything wrong with this example of a P229, or with any 'hybrid' SIG. But a potential purchaser who is new to SIGs might believe this really is a 'German-made' SIG and feel justified in paying a premium for it, then feel ripped off if and when they discover the truth.

All American SIGs

As you can probably predict from the trends noted in this article, as time went on, SIG manufactured and assembled more and more firearms in the US. In 2007, US-based Sigarms was renamed SIG SAUER. By 2014, all but a few of SIG's guns were being manufactured completely in the US, including previous 'hybrid' models whose frames had been made in Germany. In 2014, SIG SAUER's CEO was quoted that his goal was to have production for all SIGs moved to New Hampshire by 2015. 'Made in Germany' will no longer appear on any part of any SIGs.

Also in 2014, SIG's German manufacturing facility surprised many by releasing a small batch of true 'Made in Germany' SIG P220 pistols, with the classic folded carbon slide and pinned breech block — but with modern German proof marks on the slide and barrel:

Surprisingly, these guns were imported by PW Arms in Redmond, Washington… and not SIG SAUER in Exeter, New Hampshire. The barrel showed a proof date of BC, meaning they'd been proofed in 2012:

SIG P220 proofed barrel with a BC (2012) date code

Nobody knows whether these parts had been in storage in Germany for more than a decade and finally assembled and proofed, or whether the German gunmakers fired up the old equipment in 2012 for a last hurrah before all manufacturing moved to the US once and for all. Either way, a few lucky buyers got their hands on a modern example of a classic German SIG that was manufactured, assembled, and proofed in Germany… and fully deserving of its 'Made in Germany' stamping.

Final Thoughts

My goal for this article was to give you enough information to easily distinguish between the following variants of SIG firearms:

1. True 'Made In W. Germany' SIGs from both the pre- and post-reunification eras.
2. True 'Made In Germany' SIGs that are manufactured, assembled, and proofed in Germany.
3. 'Made In Germany / Assembled In US' SIGs with German-made slides and frames, assembled in the US.
4. 'Hybrid' SIGs with 'Frame Made In Germany' etched on the frame combined with US-made slides, assembled in the US.
5. 'All American' SIGs made 100% in the US.

As for whether any of these variant are more desirable, more valuable, or different enough from any other to make any difference to you is completely up to you. A 'Made in W. Germany' P226 made one week before reunification is not going to be noticeably different from a P226 made one week after reunification. And a 'Made in Germany' P220 made a month or two after the October 1995 'can't say W. Germany anymore' deadline would have been made by the same people, in the same facility, using the same equipment and materials, and proofed at the same proof house in Kiel as a 'Made in W. Germany' P220 proofed one day before the deadline.

My primary goal was to help clear up some of the considerable confusion between what's a true 'Made in West Germany' SIG vs. a 'Made in Germany' SIG vs. a 'Parts Made in Germany (wink wink)' SIG, and to have a convenient place to politely link when someone wants (or needs) to know the difference. If you encounter someone who refers to them incorrectly, please be kind in how you correct them, and politely share this link.

If you have questions, comments, corrections, or other feedback, please share them in the comments below!

If you've heard someone mention proof marks or date codes when discussing a SIG Sauer pistol, but weren't quite sure what those were, then the goal of this article is to bring you up to speed. And even if you're already familiar with proof marks, maybe this article can broaden your knowledge and teach you something new.

What are Proof Marks?

Proof marks are stamps embedded in certain parts of a firearm following (and sometimes during, depending on the firearm type) its manufacturing to indicate that the firearm has been 'proven' to be able to handle the specific type of ammunition for which it was designed. In modern years, they truly do serve that purpose. But like many government regulations, their origins have more to do with self-interest than safety.

The first proof marks started appearing in 15th century France, and by the 17th century, European firearms guildsmen were heavily promoting their use — and lobbying their governments for laws requiring them — primarily to dissuade competition from non-guildsmen and scare potential purchasers away from un-proofed guns.

In 1637, after heavy lobbying from the London Gunmakers Company, a London-area firearms guild, King Charles I issued a Royal Charter setting firearms safety standards. The London Gunmakers Company set up a 'proof house' in London, and not surprisingly… firearms makers who were not part of a guild tended to fail testing more often than the guild members. Guns that passed testing were stamped with a mark representing the proof house. Over the next few decades, other countries established their own safety standards and proof houses, along with their own unique marks. Much like reciprocity of modern concealed carry permits between states, some European countries began to recognize each others' proof marks as a high enough testing standard for foreign countries' firearms to be legally imported.

Fast forward to 1914, when a number of European countries formed the CIP (Commission Internationale Permanente pour l'Epreuve des Armes à Feu Portatives) as a formal standards group to ensure consistent testing among member countries. As of 2015, the CIP includes 14 member states. In order for a civilian firearm produced in a CIP member state to be legally imported to another CIP country, it must bear the proof mark of a CIP member state (military testing standards are, predictably, different than civilian ones). The United States does not participate in CIP, but instead formed its own standards group named SAAMI (Sporting Arms and Ammunition Manufacturers' Institute). While the CIP and SAAMI do share information and cooperate, neither has a requirement regarding selling in each other's countries. Because the US is not a CIP member state, foreign guns do not need a CIP proof mark to be sold in the US, nor do US guns need a US proof mark to be sold in CIP member countries. This is an important fact that will become relevant again later in this article.

Examples of German Proof Marks

Here's an assortment of mid 20th century proof marks used through Germany's (and West Germany's) history:

The top row (a) indicates the German (or East/West German, depending on the year) city in which the proof house is located. The column marked (b) shows varios German/West German proof marks after 1945, while the column marked (c) shows German proof marks used from 1939-1945.

Here's another image showing the marks of German/West German proof houses, along with the approximate year they were first in use:

Proof Marks on SIG Sauer Pistols

Depending on it's vintage and model, you might see proof marks on a German / West German SIG's frame:

Proof mark on a West German P220 frame

Proof marks on the slide chin of a West German SIG Sauer pistol

Kiel Proof House Mark

The top proof mark indicates the Kiel Proof House. Since Kiel is only 17 miles from SIG Sauer's manufacturing facility in Eckernförde, that's the proof mark you should expect to see on a proofed SIG Sauer. Many refer to the Kiel mark as a 'squashed bug,' while others have claimed it's an oak leaf. Actually, the proof mark is based on the city of Kiel's coat of arms:

Coat of arms of Schaumburg

All true German and West German SIGs were test fired at the Kiel proof house, so the Nesselblatt proof mark is an indicator of a true German or West German SIG. I've also heard one report of the Ulm proof house's stag antler mark appearing on a the frame and slide of a 1993 SIG P226 (in addition to the Kiel mark on the slide), which would imply that the firearm required repair and re-proofing… and presumably the repair took place at a location that was closer to Ulm than Kiel. Normally, you'd expect to see the Ulm proof mark on a Walther or H&K firearm.

The German Definitive Mark and Nitro Testing

Underneath the Kiel Nesselblatt (though the order of the marks is not important), we find the image of an eagle with the letter 'N' underneath. Some incorrectly believe that the eagle mark is a remnant of Nazi-era Germany, particularly since Germany's firearms proof mark was a previously crown, and was changed to an eagle in 1939.

In actuality, the German Reichsadler (literally 'Eagle of the Realm') dates back to the eagle on the standard of the Roman Empire, and was used as a symbol of the Second German Empire as early as 1871… long before the National Socialist German Workers' Party. The same eagle design has continued its use in West Germany since 1945, but under a new name of Bundesadler, or 'Union Eagle.'

The Eagle-N mark signifies that the firearm was proofed in Germany (or West Germany, depending on when the firearm was proofed), while the 'N' indicates that the firearm was proofed using a Nitro Beschuss load. 'Beschuss' translates as 'bombardment,' 'shelling,' or 'firing' depending on context, and 'nitro' is short for 'nitrocellulose,' a highly flammable compound used to creates pressures inside the firearm higher than standard gun powder.

Sig Sauer Serial Number Date Of Manufacture

Pistols are delivered to the proof houses in their fully assembled form for proofing. For pistols, CIP standards require cartridges that generate pressure 30% higher than the standard ammunition for which the pistol is designed, so the two high pressure nitro rounds are fired through the pistol. Technicians then disassemble the pistol and examine it in a dark room using a fluoroscopic lamp, looking for magnetic flux leakage. Provided everything looks good, the pistol is re-assembled and receives the country's CIP proof mark indicating what type of test it passed (the Eagle-N or 'definitive' mark in the case of a German gun), the mark of the proof house, and marks indicating the date of the tests. The firearms is then returned to the manufacturer who can legally sell the firearm domestically or export it to another CIP country.

The 'nitro' proof mark is also referred to as the 'definitive' (or final) mark of the proof house, as opposed to a 'provisional' mark which would generally only apply to shotgun barrels in an early stage of manufacture, which are tested at proof houses to prevent the manufacturer from continuing work on defective tubes.

Date Codes

Looking back at our photo, the 'JK' under the definitive proof mark is the date code. Date codes are two-letter indicators of the year that a firearm was proofed. Major German firearms companies such as Heckler and Koch, Walther, and SIG Sauer all used a similar date code format:

German gun manufacturers used these letters in place of numbers for date codes

Using the above table, we can determine that the 'JK' date code in the photo stands for '89' — meaning this firearm was proofed in 1989… which coincidentally happened to be the year the Berlin Wall came down. This doesn't necessarily mean that the pistol was manufactured in 1989. It's quite possible the barrel was made in 1986, the frame in 1987, and the slide in 1988… but that all the parts weren't assembled together into a firearm and delivered to a proof house until 1989. Or it's possible that all the parts were actually made in 1989, and then assembled and proofed that same year. There's no way to know. A true German / West German firearm isn't technically 'born' until it's been proofed.

Note that a gun's date code is different than its serial number. It's impossible to decode a SIG serial number to determine when it was proofed, although you can try to locate the range of your SIG's serial number in this list to approximate when it was made, or call SIG Sauer with the serial number and see if they have any info in their system. Serial numbers aren't always truly representative of the chronological order of a firearm, but they can sometimes get you close. Only a date code can tell you the year of proofing.

Proofed vs. Non-Proofed 'Made in Germany' Guns

If you've read my article on West German vs. German vs. Other SIGs, you'll know that proof marks are one of the primary indicators or whether a SIG Sauer (or any other firearm) is truly 'made' in Germany (or West Germany) as opposed to assembled in the US using German-made parts… even though the parts might be stamped 'Made in Germany.' Because the US is not a CIP country, guns marked 'Made in Germany' do not need to be proofed in order to be sold here, as long as they are assembled in the US.

In my opinion, a gun without German proof marks (with very few exceptions) is not truly a German gun. Whether that actually affects the desirability or quality of the gun is for you to decide. But you should at least be aware that for most SIG purists, the existence of proof marks is what determines whether a gun is correctly referred to as 'Made in Germany.'

Putting it All Together

Now that you know how to decode proof marks and date codes, see if you can figure out where and when the following firearms were proofed. Most are SIGs, but I threw some other German guns in there just for fun. 🙂

Normally, the proof house mark is above the definitive mark on a SIG, but this is a very early SIG P220

Sig Sauer P365 Serial Number Lookup

Walther P99

Opf files. The long-term records in the file are included to protect the legal and financial rights of the government and the employee.

I welcome your corrections, questions, comments, & feedback below.

Further Reading:

Sig P220 Serial Number Dating Line

Sig Sauer P220 Manufacture Dates

• http://firearmshistory.blogspot.com/2011/01/testing-firearms-proof-test.html
• https://en.wikipedia.org/wiki/Proof_test