1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

K, N, J frame revolvers??

Discussion in 'Handguns: Revolvers' started by Mokwepa, May 13, 2009.

  1. Mokwepa

    Mokwepa Well-Known Member


    Can someone please explain the differance in frames between the K N J frame revolvers? I have no idea what this is, i presume its size.

    I have a Astra Inox 2" snubby ss 38spl, what would that compare to? I think my Astra is a 680 but its only a 5 shot.

    Any ideas where i can get som info on my snubby, i have serched the net but have found nothing, they dont seem to be very common or popular.

  2. KBintheSLC

    KBintheSLC Well-Known Member

  3. SaxonPig

    SaxonPig Well-Known Member

    S&W system for denoting frame size. The J is the current smallest used for guns like the 5-shot 38 caliber Model 36 "Chiefs Special."

    The K is the classic .38 Special size used for the Model 10 "Military & Police" models and many other models as well. Some 357 Magnums were built on the K but there were concerns about strength.

    So the L frame came out. Just a tad sturdier than the K.

    The N is the 44 size frame, used for the heavy 357 Magnums (Models 27, 28 for example) and the 41 and 44 Magnums and others.

    The X frame is the huge guy for the 500 caliber.

    Older discontinued frame sizes include the I frame and a couple others.

    I frame:


    J frame:


    K frame:


    I don't have an L frame. Sorry.

    N frame:


    The S&W frame sizes may not exactly correspond to those of other manufacturers. You can sort of guess at which are appropriate comparisons by the caliber and physical size. I suspect your 5 shot Astra would most closely approximate the J frame.
  4. rcmodel

    rcmodel Member in memoriam

    I & later J-Frame = started out as a .32 and is now most often a 5-shot .38 or .357, or 6 or 8 shot .22.

    K-Frame = started out as a 6-shot .38, and still is. Also has been made in .22, .32, .357, and a few other calibers smaller then .38.

    N-Frame = started out as a 6-shot .44 and still is. It has been used for .38 Spl, .357 Mag, .41 Mag .44 Spl, .44 Mag, .45 ACP, and .45 Colt, among other things.

  5. Mokwepa

    Mokwepa Well-Known Member

    Man you gays are good!!

    Sorry i didnt look at s&w sight untill now.

    Thanks for clearing that up.

  6. krs

    krs Well-Known Member


    "N" frame on top; "J" frame on bottom.

    In between the two are "K" and "L".
  7. krs

    krs Well-Known Member


    Lemme' see.........the two top are both "N" frame.
    The middle two are "J" on the left, "K" on the right.

    The bottom two define the difference between a round butt on the left and a square butt on the right. Both are "J" frame revolvers.
  8. krs

    krs Well-Known Member

    Well now, Saxon Pig is an easy call, but RC? Who'd have thought? :D
  9. CorpITGuy

    CorpITGuy Well-Known Member

    Very informative post. Thanks to the OP for posting, and the "gays", er, guys for replying. I learned something. :D I knew what a J-frame was, never heard of the others...
  10. BlindJustice

    BlindJustice Well-Known Member

    +1 Saxonpig

    To put dates on the frames:

    K frame had origins in
    1899 1rst model hand ejector in .38 Special
    This later was called the Miltary & Police
    and got the MOdel 10 desgination in 1957 when
    S&W put the 2 digit designation on all of their
    N Frame
    1908 2nd MOdel Hand EJector .44 SPecial
    used for the US Military M1917 in .45 ACP s/moon ckps
    1935 1rst chambering for .357 Mag
    1955 1rst chambering for .44 Mag
    Model 29 aka Dirty Harry model

    L Frame - early 1980s
    Beefed up - greater length for a sturdier .357 Mag
    medium frame.

    J-frame - post WWII
    S&W Beefed up the I frame and unlike the other
    frames which use a leaf main spring the J frames have a
    coil main spring

    & the Largest, the X frame for .500 S&W and .460 XVR

  11. Oro

    Oro Well-Known Member

    KRS - are the grips on the pre-27 in your first photo newer reproductions? From whom, if so?
  12. krs

    krs Well-Known Member

    That's not a pre 27, it's a Lew Horton redo of the registered magnum in eight rounds. Those grips are new, came with the pistol, and probably were made by the same folks who make the grips that S&W buys for their 'classics' line of reproduction, or reborn, older models.

    I don't know who made them for sure, and they aren't maker marked inside anywhere.
  13. Thingster

    Thingster Well-Known Member

    That's awesome, it's exactly the gun I wish S&W made right now. An 8 shot N frame .357 that looks just like a 27 otherwise.

    Sexy man, sexy.
  14. Oro

    Oro Well-Known Member

    OK, got it now. The sideplate screw and worn looking finish (now I presume the lighting and angle) threw me, but I recognized them as newer grips. i want a pair of those for a 27-2 I have so I can "stash" the excellent orig. grips for the few times I actually carry it.

    Do those grips fit the frame well? I have seen variable fit/finish on some of the wod grips on the new "classics." Those look pretty darn good. Do you like them compared with the older quality ones, say, pre-1980?

    (Sorry for the thread drift)
  15. ArchAngelCD

    ArchAngelCD Well-Known Member

    I just love show-n-tell threads. Nice pictures Saxon, I don't recall seeing those revolver before.
  16. Mokwepa

    Mokwepa Well-Known Member

    Oh hell im sorry about the "gays" thing, only realized it now. I was wondering what you were all on about. Sorry again. :)
  17. Stainz

    Stainz Well-Known Member

    Just a few words to clarify why an L-frame was developed. There was nothing wrong with the original K-frame .357 Magnums - with SAAMI-spec'd ammo in heavier bullet weights (140-158 gr). As you go lighter, of course, the velocity increases. This made 110-125 gr .357 Magnum bullets require 'hot' propellants - producing more hot gases escaping at the b/c gap - and possibly eroding the smallish forcing cone. While cracked forcing cones undoubtedly occurred, they can be fixed by a barrel change. This likely would never occur in normal use, as it was estimated as taking 20k lite/hot loads minimum to cause this damage. There are millions of 13, 19, 65, & 66 models, all K-frames, still in use - and great .357 Magnums, too.

    The L-frame has a front frame piece that is .040" thicker where the barrel mounts. This permits a .025" larger OD on the barrel - and more 'meat' at the .357 Magnum's forcing cone. They also gave it a taller cylinder opening - allowing a 7-shot cylinder to be fitted. This also permitted a 5-shot .44 Special variant to fit the frame, albeit with a really teeny forcing cone (No Keith-level loads for these .44 Specials!). The gripframe of the L-frame is the same size as the K-frame, thus, they take the same sized grips. Several years ago, S&W dropped the last of the K-frame .357 Magnums, the 65 & 66, and replaced them with 7-shooter 619 & 620 models. As the other .357 Magnum L-frames were full-lugged, they appeased we traditionalists with the 619/620 models and retained the partial lugs of the 65/66 models they replaced. Gripped similarly, a 4" 66 and 620 aren't too different... great 'pointers'.

    The K-frame won't go away... the original M&P's latest variant, the 10, may always be in the S&W line - as is it's SS sibling, the 64 - and the adjustable sighted version, the 67. Then there is my latest new one - a 617 from last fall. That's a ten-shooter in .22 LR.

    You can have fun in one caliber - .38 S&W Special - with each frame size. A J-framed 642 as a five-shot pocket protector, a 4" 64 as a K-frame plinker/house gun, a 5" half-lug 686+ as a fun seven-shooter plinker, and a 4" 627 Pro eight shooting, N-framed, super-fun plinker. Yeah, I won't ever bring them all to the range at the same time again - the indecision as to which to shoot was maddening! Also, I shot up a ton of my 125gr JHP .38's.

  18. krs

    krs Well-Known Member

    Hi, the grips fit good enough but they lack the ambience of an older set and thus seem sort of fone'., if you catch my drift.

    I don't use them for shooting the pistol because they cause my knuckles grief, but I like their smaller size making the rest of the revolver look so huge! They'd be better with a Tyler T grip filler.

    I have fingergrip Kim Ahrend's grips on the gun most of the time and take it with me when it's chilly enough to hide it.

    edit: it's the same revolver as top left in my second photo, that time with Ahrend's non fingergrip square butts. I switch grips around as it strikes me to do, as I'm pretty sure you like doing as well, Oro.
  19. SaxonPig

    SaxonPig Well-Known Member

    Here's a K frame Magnum shipped in 1970 to the federal government. I bought it 18 years later from the retired federal agent who said it had been fed nothing but full power 125 JHPs and that's what I shoot in it. So far, nada. Some K frames have failed with various ammo types (1 split the barrel with target 38 loads) so I am not sure that it isn't some defect in select guns rather than a general unworthiness of the whole line.


    The new "classic" stocks will generally fit the older models. Here's a pair of 3rd model 44 Specials wearing the new Service Stocks sold for $55 from S&W.


    Also, the L frame guns use the same stocks as the K frame models.
  20. BlindJustice

    BlindJustice Well-Known Member

    Stainz gets a +1

    For the O.P. many of the S&W aficiondos refer to various
    models by only the model number but they all also have
    a title.

    The model 36, blued carbon steel and the ( first production
    handgun in ) stainless steel MOdel 60 = Chiefs Special.

    K frames
    Model 10 - Miltary & Police
    Model 15 K-38 Combat Masterpiece - it has ramp
    front and adj. rear in .38 Special with standard hammer
    & trigger. 4" Barrel
    Model 18 K-22 .22 LR version of the Model 15
    MOdels 14, .K-38, .38 Special Model 16 K-32
    in .32 S&W and MOdel 17 .22 LR are the Target
    Masterpiece, with 6" or 8 3/8" bbl.s and larger/wider
    Target trigger and hamer

    Model 19 Combat Magnum
    MOdels 581/586 681/686
    Distinguished Combat Magnum

    & so on.... all i can pull out of ready memory
    but it's a good exercise I'd have to look up the 27
    but the 28 was named Highway Patrolman - both N-frames
    the 28 meant for LEOs as a working gun, and the 27
    being the top finish - jhigh polish blued and polisheed
    interior parts as well.

    oh, gotta do one of my favorites,

    Model 25 1955 Target .45 ACP/.45 Auto RIm


Share This Page