sig p210 trigger function

The SIG S.P.47/8 was developed to compete for succession of Georg Luger’s Parabellum pistol that had been adopted by the Swiss Army in 1900 as the first automatic pistol to be issued in military service. Although the Luger has been simplified, and arguably perfected in its 1929 embodiment by the Waffenfabrik Bern (W+F), it was deemed too expensive for continued production. Its successor was to cut down on the costs while maintaining its stellar accuracy. The legacy of the Luger is clearly seen in one of the modifications of the Charles Petter design that SIG licensed for that purpose in 1937. While Petter’s Modèle 1935A pistol imitated the M1911 in its slide rails riding on tracks in the frame, SIG replicated the Parabellum arrangement that made the upper assembly reciprocate inside the frame tracks. Sig also designed a two-stage trigger that imitated the trigger pull of the Luger, while decreasing its trigger weight, as witness the following test results.
    On the Lyman electronic trigger gauge, the trigger of a heavy frame SIG P210-6, serial number P79608, yields a weight of 1.2kg, averaged over 10 pulls. Its immediate heavy frame successor, P79609, fitted with a National Match hammer, releases the sear at an average of 1.23kg. Likewise the heavy frame P210-6, serial number P79103 in 7.65 Para, at 1.24kg. That’s about as good as you can get in a tuned service grade self-loading pistol, and much lighter than Swiss pistol target shooting competitions allow, by requiring a trigger weight above 1500 grams. More typical are the measurements of the heavy frame SIG P210-6, serial number P79136, which yields a weight of 1.82kg, averaged over 10 pulls, the Borchardt C93, serial number 1774, releasing the striker at 2.59kg, and the Krieghoff P08, serial number 3249, weighing in at a hefty 3.48kg.
    More Swiss service pistol trigger pull weight measurements follow:

  • P06/1929 SN 71644: 3.80kg;
  • P06/1929 SN 77493: 2.57kg;
  • P06/1929 National Match SN 59951: 2.64kg;
  • P06/1929 National Match SN 65721: 2.15kg;
  • P210-6 SN P86618: 1.78kg;
  • P210-2 SN P79980: 1.67kg;
  • P210-1 SN P77209: 1.94kg;
  • P210-2 SN P74064: 1.86kg;
  • P49 SN A204931: 2.88kg;
  • P49 SN A156213: 2.90kg;
  • P49 SN A107159: 2.75kg;
  • P49 SN A105553: 2.56kg.

All are two stage, with a very crisp stage transition (Druckpunkt). It is obvious which pistols have been resprung. As witness P06/1929 National Match SN 59951 and 65721, W+F was either unwilling or unable to equal, let alone best the measurements of a factory tuned P210, in preparing for the 1949 ISSF competition in Buenos Aires.
    The double pull lever is the part responsible for regulating the transition between the two stages of the trigger pull of the P210. After the trigger, part #28, takes up the slack to engage the sear, part #23, by way of the trigger rod, part #26, the first stage of the trigger pull is determined mainly by the weight of the trigger spring, part #31, with additional resistance provided by the sear spring, part #24. As the sear rotates around its pin, part #22, it brings all the way back the hammer, part #14, and contacts the double pull lever, part #21. At that point, the double pull lever connects the sear with the mainspring, part #20, providing considerable additional resistance in the second and final stage of the trigger pull, just before the release of the hammer by the sear.

    Double pull lever adjustment method
click on the picture for higher resolution

    The double pull lever is individually hand-fitted to the sear and the hammer to regulate the pressure point (Druckpunkt) of the two-stage trigger pull system. If the pressure point is too soft, i.e. if the second stage of the trigger pull has to be strengthened, the top surfaces of two support arms furthest away from the pivot pin of the double pull lever, part #22, must be evenly worked down with an oilstone at the point of their contact with the hammer action housing, part #13. This operation brings the body of the double pull lever closer to the sear. In performing this operation, both sides of the double pull lever must remain perfectly square at the points of their contact with the hammer action housing. The hammer action housing itself should not be modified. If the pressure point is too hard, i.e. if the second stage of the trigger pull has to be weakened, the two projections in the middle of the double pull lever located on either side of the stirrup, part #16, must be evenly worked down with an oilstone at the point of their engagement by the sear, part #23, in the course of the trigger pull. This operation postpones the engagement of the double pull lever by the sear. In performing this operation, both projections on the double pull lever must remain perfectly square at the points of their contact with the sear. The sear itself should not be modified. Never attempt any modification of these parts, unless you are certain of your gunsmithing competence.
    In late production, forged and deep hardened milspec sears and double pull levers were gradually replaced by metal injection molded (MIM) parts of slightly modified profiles. This image is taken from Armbruster, p. 193:

    Double pull levers used during the SIG P210 production runs. Nos. 1-4 are milled and hardened. From No. 2 the area between the anterior and posterior pressure ridges was reinforced by adding material. No. 5 is the latest version, produced by metal injection molding.
click on the picture for higher resolution

As with all MIM components, these parts are superficially case hardened. They are therefore unsuitable for hand fitting that is liable to cut through the hardening and expose soft core metal in the working surfaces.

fill your hand!

Symmetrical wraparound Nill grips on the recently produced Korth revolvers are ambidextrous and nicely hand-filling. I am getting the last two made by Nill for post-1986 Korth revolvers, and have their likes installed on my five favorite Manurhin MR73 revolvers. Original Korth stocks have an open backstrap and a shallow thumb rest just big enough to block a speedloader. They offer a nice rolling fit for the right hand; not so good for the left. Korth revolvers have two kinds of gripframes: the square butt frame on the Sport and Match revolvers, and the rounded butt gripframe on the Combat models. Since every revolver is benchmade individually, factory stocks are hand-fitted to each gun, and cannot be expected to interchange between them, much like the original Magna stocks on S&W Registered Magnums.

The Manurhin MR73 has a uniformly dimensioned, compact grip frame in a true round butt configuration. There are two kinds of factory stocks for the MR73. Most of the early revolvers regardless of the model, and most of the Police and Defense models regardless of vintage, are fitted with abbreviated walnut stocks that follow the contours of the grip frame, except for filling the gap behind the trigger guard in the manner of the pre-WWII S&W grip adapter. They are very comfortable to hold, but require a very firm grip for controlling the roll under recoil, and provide little feedback for a consistent handhold. The factory walnut, symmetrical finger grip Sport stocks fitted to later production Sport and Gendarmerie models wrap around the front strap and extend past the butt in a squared configuration, exposing the typically grooved backstrap. They are more hand-filling and offer better indexing, albeit not to the degree afforded by Nill grips. Full wraparound Trausch rubber grips, which can be had with or without a shelf at the bottom, offer all advantages and drawbacks of their kind.

No revolver designed and manufactured in the U.S. after 1911, was intended or suited for combat, as that destination was interpreted by the makers of Webleys and Nagants. Owing to America’s late entry into WWI, none of them were widely and successfully used in trench warfare, in the manner of the LP08 Artillery Luger. Like the S&W M19, its delicate precursor, the MR73 was designed and built for fighting by the constabulary personnel, not for combat by the military. Its typical application took place on the day after Christmas of 1994, when Captain Thierry P. of GIGN entered the hijacked Air France Flight 8969 plane, grounded at the Marseille airport. He served as the point shooter, armed with a 5¼" .357 Magnum Manurhin MR73 and backed by his partner Eric carrying a 9mm HK05 submachine gun. Thierry killed two Islamist terrorists and wounded a third with his revolver, before taking seven bullets from an AK47 fired by the fourth hijacker. In spite of then absorbing a full complement of grenade shrapnel in his lower body, Thierry P. survived the assault, as also did 171 hostages. Not so the four terrorists, who had been planning to deploy the plane as an incendiary missile against the Eiffel Tower. Thierry could have armed himself with any firearm. He chose an MR73. His fellow GIGN intervention troopers still choose to carry their vintage Manurhin MR73 revolvers alongside a modern automatic pistol such as a Glock G17 or G19, or a SIG P228 or P2022. Such anecdotes add up to all the data at my disposal, attesting to the relevant user preferences. N.B.: The plural of “anecdote” is “data”.

korth revolvers ride again

In reference to increments cited on, Jeff Cooper wrote:

In rifle work group size is of some interest, but it is by no means the critical consideration that some commentators seem to deem it. It is well to remember that a rifleman does not shoot groups, he shoots shots. A tight group is nice, but one must not fall into the error of PII (Preoccupation with Inconsequential Increments). I have shot a great deal in a long shooting life, and I have only once encountered a rifle that would not shoot better than I could shoot it. (That was a 32-20 lever gun which had been allowed to rust and then scraped out. In getting the rust out of the barrel, most of the rifling went along with it.)
    Group size is unimportant, unless it is very bad. If you can hit a dinner plate, first shot, every time, under all conditions, at 100, that will do.

I am sorry to say that this nugget of cantankerous cogitation is cute but dumb. Three years ago, its daft but pervasive notion of a gun that shoots better than the shooter inspired me to write this post. To summarize its argument, any mechanical looseness built into your handgun in order to ensure its reliable operation, compounds your errors of aiming, shooting, and following through. Any additional degree of slop caused by stacking production tolerances will degrade your shooting performance, regardless of its level.
    Furthermore, imperious imputations of unimportance to this or that aspect of our avocation, are both unapt and un-American, even when announced by anointed authorities. It may please you to “hit a dinner plate, first shot, every time, under all conditions, at 100”; but that has nothing to do with realizing my interest in doing likewise to a barn door or a silver dollar. We live in a free country, where it behooves everyone to formulate his own goals in the pursuit of happiness, and everyone else, to stay out of his way, inasmuch as he reciprocates in kind.
    Lastly, in the issue at hand, the consequential increment relates not to accuracy, but to ruggedness and durability. I have some remarkably accurate guns, which include two of my favorite centerfire target pistols, the long-barreled W+F 06/29 Swiss Lugers from the 40 pistol Swiss National Match production run for the 1949 ISSF competition in Buenos Aires, won by Heinrich Keller, as discussed in my article linked above and shown in the photo reproduced below. Korth revolvers are not dedicated target guns that distinguish themselves along the same lines. They are optimized for other qualities, which may or may not serve your interests in shooting. Don’t rely on reviewers. Find out what’s important for you, and do as you see fit.

Heinrich Keller of Frauenfeld, Switzerland, aged 40, representing his country with a specially constructed 170mm-barreled W+F 1906/29 7.65mm Luger in his first international event, the 1949 ISSF competition in Buenos Aires.

colt government model vs dwm luger p08

One of my favorite handguns is a 1939 National Match Colt Government Model. It is the first shootable M1911 pattern gun that I ever came across. I call a gun shootable if it throws bullets where I aim it, with high precision and little fuss. All other M1911 handguns that I fired either made too much fuss for my taste or fell short of my expectations for precision. I consider a handgun fussy if it cannot be counted upon to fire 200 rounds fast without acting up. I do not consider it precise unless it can consistently hit a silver dollar at 75 feet. My Colt can do both in style. Most of its brethren fall short in one way or another. Continue reading colt government model vs dwm luger p08