Springfield Armory's 1911 serial number prefix

Discussion in 'Beginner's Corner' started by Quack, Aug 16, 2011.

  1. Quack

    Quack it's mmm, mmm good... Admin

    Joined:
    Aug 15, 2011
    Messages:
    4,146
    Location:
    NE Ohio
    A lot of debate has gone around on the internet about what the "NM" serial number prefix stands for. Some believe that it stands for "National Match", which is typically the case when you see that marking, however it's not so with Springfield 1911's. It is well known that Springfield Armory Inc. 1911's start from IMBEL forgings from Brazil. The 1911's that have the "Brazil" import marking's on the frame have more than 50% of the work performed by IMBEL, these would have the "N" prefix. The GI's are also made in Brazil and have the WW prefix. The Mil-spec model's can have either a N or NM prefix, with the N being more common.

    Springfield's Loaded models, could either have the N or NM prefix. Model's with the N prefix are imported almost complete with the exception of the sight and beavertail grip safety cut's. These cuts are done at Springfield's facility in Geneseo, IL. The NM prefix Loaded's (as well as the Range Officer, TRP and Trophy Match) have the magwell and most of the internal cuts done, but no rail cuts. The final CNC machining on NM prefixes is done in Illinois. This information was from this article.


    The rest of the 1911 prefixes such as LW, TGO-2, TGO-3 and EMP all come from Springfield's Illinois facility, though I have seen some older LW's marked "Brazil". The Custom Shop gun prefixes such as CRG, FBI, DEA, and TGO-1, as well as any other Custom Shop marked gun, are also made in Illinois. According to Springfield, the Custom Shop marked guns are built using "National Match" frames.

    Is there a difference in build quality? In my opinion/experience...yes. In general the NM marked guns have a better frame/slide fit, than the similar model with a N prefix. Other's on the internet tend to look for the NM marked 1911's as well.
  2. knedrgr

    knedrgr Low capacity, low tech... Moderator

    Joined:
    Aug 15, 2011
    Messages:
    3,618
    Location:
    NE Ohio
    SA N vs SA NM guns

    While at a LGS today, I saw that they had a SA Mil-Spec parkerized. And then saw it was a NM marked gun. So I had to check it out. durning was this thing nicely put together. The frame and slide was tight and rolled on bearings. Barrel locked up was really nice, and it took some effort to break it out of battery. This is also true for Quack's SA Mil-Spec NM gun.

    Having own a SA Mil-Spec SS, and it's a N marked gun, it's completely night and day between the two guns. After a trip back to SA, and a barrel replacement (under warranty) my MS has the same lock up tightness as the NM marked gun. However, my MS slide is still looser and not as nicely machined as the NM ones.
  3. Sir Guy

    Sir Guy Sharpening Ockham's Razor Forum Supporter

    Joined:
    Aug 20, 2011
    Messages:
    1,937
    Location:
    Missouri
    I've thought about getting one of them as a beater/loaner 1911. If nothing else, I really like the look of them.

    The Guncrafter is nice. Aesthetically, the Series 70/Mil-Spec guns are my favorite profile. On some emotional level, they're how I always think of 1911s. :smilie:

    Andy
  4. SkDmRkLcY

    SkDmRkLcY Active Member

    Joined:
    Aug 17, 2011
    Messages:
    1,437
    Location:
    SW Ohio
    I have not seen a Mil-Spec or GI for sale in ages around here. I am pretty sure if I did see a NM one I would pick one up for a base gun over the Colt I currently have in that slot. I also do not like the made in Brazel dust cover. I do not care that it was... Just do not stamp it like that.

    The Colt has a good barrel fit, but the slide to frame is not super tight.
  5. CMG

    CMG Member

    Joined:
    Aug 20, 2011
    Messages:
    848
    I've had the opportunity to compare an N and NM 9mm loaded with Novak sights at the same store and I have also found the NM guns to be superior in fit.
  6. 3rdgen40

    3rdgen40 New Member

    Joined:
    Sep 2, 2011
    Messages:
    13
    Location:
    Arkansas
    Some say there is no difference, but there is a huge difference.I have owned 2 S/A Mil-Specs.One was an N and the other was an NM.The NM was much smoother and tighter.Slide to frame fit was way better.Lock up was much tighter.I would never buy another S/A that was put together in Brazil.
  7. Quack

    Quack it's mmm, mmm good... Admin

    Joined:
    Aug 15, 2011
    Messages:
    4,146
    Location:
    NE Ohio
    one main difference is that the rails are cut in the US and not in brazil. I have a pair of Brazil guns, but they aren't the best to judge because they both went to SACS for work. the .38S slide is on the loose side, but the 9mm top end was fit specifically to the frames, so it's nice and tight. my NM is totally different than knedrgr's N marked gun. his was rough and gritty when new, while mine is smooth, my barrel fit was much nicer too.
  8. Nick

    Nick Member

    Joined:
    Aug 22, 2011
    Messages:
    147
    Location:
    OK
    Wait, so NM's are assembled differently from N's?
  9. Kokopelli

    Kokopelli Schütze

    Joined:
    Aug 17, 2011
    Messages:
    2,162
    Location:
    East Tennessee
    From my experience.. In general the NM#'s have a better fit and the machining is cleaner. There are exceptions as my longslide (N#) had a very good fit and outward finish. The internal machining showed more machine marks and the ramp was a little rough. My first encounter was when shopping for my first 5" SA. The stainless loaded's I saw were rough and loose while the loaded target's were much better. A lot of it was just the difference between pistol "a" and pistol "b". Shopping and looking over several can have advantages.. Ron
  10. CMG

    CMG Member

    Joined:
    Aug 20, 2011
    Messages:
    848
    Yes:

    N marked guns have the majority of their assembly completed in Brazil.

    NM marked guns have the majority of their assembly completed in the US.
  11. Jim S.

    Jim S. Evil Capt. Kirk from G.T.

    Joined:
    Aug 25, 2011
    Messages:
    74
    Location:
    N.W. Indiana
    I have two N Mil-Specs and one NM Mil-Spec.
    I have found that the NM is definately tighter in the slide to frame fit, but also in some other areas that I don't care for.
    The thumb safety is difficult to remove compared to the N guns.
    The main spring housing is tight and needs to be pryed out of the frame.
    The trigger does not slide out freely.
    All easy to fix stuff and no big deal really but...
    The one that I don't like is that the NM slide over hangs the rear of the frame when it is in battery.
    Not by much but still noticable.
    The N guns are perfect all around.
    Maybe I got two perfect N Mil-Specs, or I got a not so perfect NM Mil-Spec.
    They all shoot very good and are dependable running guns with all of the ammo I've tried so I am happy with all three guns.
  12. Kokopelli

    Kokopelli Schütze

    Joined:
    Aug 17, 2011
    Messages:
    2,162
    Location:
    East Tennessee
    That would seem to be the case.. Cheers.. Ron
  13. Nick

    Nick Member

    Joined:
    Aug 22, 2011
    Messages:
    147
    Location:
    OK

    Wait, Springfield makes guns in Brazil??
  14. Kokopelli

    Kokopelli Schütze

    Joined:
    Aug 17, 2011
    Messages:
    2,162
    Location:
    East Tennessee
    Mine speak Portuguese, but they all have Spanish names.. Ron
  15. 38 Super Fan

    38 Super Fan Bass Fishing Addict

    Joined:
    Aug 18, 2011
    Messages:
    494
    Location:
    KY
    There is no TGO prefix is there?
    Last edited: Sep 6, 2011
  16. Quack

    Quack it's mmm, mmm good... Admin

    Joined:
    Aug 15, 2011
    Messages:
    4,146
    Location:
    NE Ohio
    It's a RL prefix
  17. elsilrac1

    elsilrac1 New Member

    Joined:
    Sep 5, 2011
    Messages:
    5
    Location:
    Near Little Rock AR
    Just picked up a NM marked milspec. I cant wait to shoot it.
  18. Quack

    Quack it's mmm, mmm good... Admin

    Joined:
    Aug 15, 2011
    Messages:
    4,146
    Location:
    NE Ohio
    congrats!!!
  19. Dumbell2

    Dumbell2 Member

    Joined:
    Sep 7, 2011
    Messages:
    129
    Location:
    Houston, TX
    Great score!
  20. Sir Guy

    Sir Guy Sharpening Ockham's Razor Forum Supporter

    Joined:
    Aug 20, 2011
    Messages:
    1,937
    Location:
    Missouri
    Nice grab! Stainless or parkerized?

    Andy

Share This Page