How are Sako 75 and 85 actions made?

Discussion in 'Sako 75, 85 and A7' started by pentzer, Feb 20, 2020.

  1. pentzer

    pentzer Member

    Messages:
    23
    Likes Received:
    0
    Country Flag:
    USA
    State/Region:
    US Idaho
    Hi, does anyone know how Sako 75 and 85 actions are made? Are they cast or forged or machined out of a billet? I know the older L461 and 579 actions were forged.

     

  2. P04R

    P04R Well-Known Member

    Messages:
    155
    Likes Received:
    24
    Country Flag:
    Finland
    State/Region:
    European Union
    They are all machined out of round stock. 75 and 85 bolts are machined out of forged blanks.

    In the days of L46 or L469 they tried casting a prototype batch of receivers on their precision casting line, but this turned out to be not viable. I believe they thought the strength wasn't good enough with the cast steel.
     
  3. paulsonconstruction

    paulsonconstruction Sako-addicted

    Messages:
    2,886
    Likes Received:
    334
    Country Flag:
    USA
    State/Region:
    US Iowa
    Other than the prototype investment casting Sako experimented with, as mentioned by PO4R, all Sako actions were machined. I don't know how you could "know the older L461 & L579 actions were forged" when that never occurred. Sako went to CNC machining in 1985 & continues to use that method on their current models.
     
  4. icebear

    icebear Well-Known Member

    Messages:
    815
    Likes Received:
    355
    Country Flag:
    USA
    State/Region:
    US Arizona
    Having seen the rows of gleaming, sparkling-clean CNC machines at the Sako factory, I can confirm the above.
     
  5. pentzer

    pentzer Member

    Messages:
    23
    Likes Received:
    0
    Country Flag:
    USA
    State/Region:
    US Idaho
    Thanks for the info. I must have read some mistaken info in one of my gun magazine articles. I stand corrected. I am not only a Sako Collector but also a Winchester Model 70 collector. They are a true forged action.
     
  6. paulsonconstruction

    paulsonconstruction Sako-addicted

    Messages:
    2,886
    Likes Received:
    334
    Country Flag:
    USA
    State/Region:
    US Iowa
    There is no such thing as a "true forged" action. The definition of "forge" is to make or shape a steel object by heating it in a fire or furnace & then beating or hammering it. The initial steel billet that the action is made from is "forged", or mechanically extruded, as is all raw steel, but the action itself is machined. The exception would be Ruger & possibly others that use an investment casting process to make their actions. Knives, axes, & other simple objects can be "forged", but not actions. Whoever told you any action is "forged" is using the wrong terminology or confusing "forging" with casting. Gun magazine writers & gun advertisement people aren't good sources for info about making or processing steel. I doubt anybody pounds out actions from hot steel with a hammer. Just sayin'.
     
  7. pentzer

    pentzer Member

    Messages:
    23
    Likes Received:
    0
    Country Flag:
    USA
    State/Region:
    US Idaho
    Quote taken from a wikipedia article on Winchester models 70 post 64 actions. The receiver, for the first time, and from here on out, was forged into shape, then machined. Heat treatment of the receiver was localized to the areas where necessary, namely the cams and locking lugs, to prevent warping caused by overall heat treatment. Forging the receiver increased its strength and reduced the machining labor and time needed to achieve the final shap
     
  8. pentzer

    pentzer Member

    Messages:
    23
    Likes Received:
    0
    Country Flag:
    USA
    State/Region:
    US Idaho
    I know what a forge is. I am a fourth generation farmer/rancher. My great grandfather and grandfather were good blacksmiths who made parts with metal to fix equipment. My father had a forge set up in our shop and used it to shape metal. I am quite aware what forging is.
     
  9. paulsonconstruction

    paulsonconstruction Sako-addicted

    Messages:
    2,886
    Likes Received:
    334
    Country Flag:
    USA
    State/Region:
    US Iowa
    Winchester went to sintered steel after 1964 for it's actions and many other parts. Sintering is the process of making a solid steel shape from powdered metal using heat & extreme pressure applied thru a hydraulic press. Sintering can form the outside shape & eliminate some machining. The interior & the rest of the action was then machined. Sintering results is a less strong steel, but adequate for it's intended purpose. I hardly consider Wikipedia an authority on everything & believe it, or it's contributors, could be confusing the sintering process with forging. Just because something is on the internet doesn't make it true. Regardless, everybody is entitled to believe what they want.
     
  10. pentzer

    pentzer Member

    Messages:
    23
    Likes Received:
    0
    Country Flag:
    USA
    State/Region:
    US Idaho
    This taken from Winchester's website "The forged steel receiver starts as a forged from a solid block of steel. (What could be stronger?) This is expensive to do, but the regal Model 70 is worth it. Each finished forging is precisely machined, creating a strong, stiff and solid receiver that resists flexing and delivers uncanny accuracy. The bottom profile of this receiver is flat to offer greater surface area for bedding. It is bedded with a two-part epoxy in two places, at the front and rear to keep things from shifting around inside the stock during firing. Why all this trouble and time? So pinpoint accuracy is preserved."
     
  11. pentzer

    pentzer Member

    Messages:
    23
    Likes Received:
    0
    Country Flag:
    USA
    State/Region:
    US Idaho
    Words taken from a blog site from an engineer."Forging is king if you want a really tough part. For fracture resistance, arguably the main consideration with a firearm frame, forging aligns the grain structure to follow the surface, which helps resist crack propagation. With hot working you’ll also get a fine grain structure."
     
  12. stonecreek

    stonecreek SCC Secretary Forum Owner SCC Board Member

    Messages:
    6,784
    Likes Received:
    853
    Country Flag:
    USA
    State/Region:
    US Texas
    I think that's exactly what Paulson has been saying. A "forged" receiver comes from a hunk of steel that is forged in approximately the size and shape of the finished product, then machined, either by hand or by automated machinery, to its final dimensions. The closer to the final size and shape the forging, the less machining there is to do. But the hunk of steel which is the forging looks more like a bar of steel with the rudimentary shape of a rifle receiver than like an actual receiver -- lots of metal has to be removed from the forging to make it into a receiver by machining it.

    On the other hand, an investment cast receiver (Ruger pioneered this method, I believe) is very close to its finished shape and only requires a relatively light machining clean-up of the rough edges to get it to finished dimensions.

    Round actions like a Remington 700 are simply heavy pipes made of higher-grade steel that only needs the openings for the magazine and loading port cut plus the various mounting holes drilled and barrel threads tapped.
     
  13. pentzer

    pentzer Member

    Messages:
    23
    Likes Received:
    0
    Country Flag:
    USA
    State/Region:
    US Idaho
    Winchester went to sintered steel after 1964 for it's actions and many other parts. Sintering is the process of making a solid steel shape from powdered metal using heat & extreme pressure applied thru a hydraulic press. Sintering can form the outside shape & eliminate some machining. The interior & the rest of the action was then machined. Sintering results is a less strong steel, but adequate for it's intended purpose. I hardly consider Wikipedia an authority on everything & believe it, or it's contributors, could be confusing the sintering process with forging. Just because something is on the internet doesn't make it true. Regardless, everybody is entitled to believe what they want.

    Hawkeye Bottoms- Iowa, USA

    No that is not what he is saying. Sintered steel is quite the opposite of forging from a "solid block of steel." as in the quote I quoted. Completely different.
     
  14. pentzer

    pentzer Member

    Messages:
    23
    Likes Received:
    0
    Country Flag:
    USA
    State/Region:
    US Idaho
    I guess the question is, Are Sako actions machined from steel that has been forged or is it just bar stock? Forging changes the molecular structure of the steel. Bar stock can be heated to "heat treat" it. That hardens the outside of the metal but does not change the molecular structure of the steel inside. That is the way a Remington action is done. Winchester actions are heated up and pounded into a rough shape before machining like you said. Back to my original question, I have read that the older Sako actions were made from forged metal. That may be incorrect. However, before I lay down a bunch of money for a firearm, I would like to know.
     
  15. stonecreek

    stonecreek SCC Secretary Forum Owner SCC Board Member

    Messages:
    6,784
    Likes Received:
    853
    Country Flag:
    USA
    State/Region:
    US Texas
    Okay, I understand you now.

    You believe that a website describing production methods in 2020 -- after the Winchester brand has changed not only owners four (or is it five?) times but moved its manufacturing plant three times -- provides evidence of how rifles were made by its predecessor over a half-century ago.

    I don't think I can help.
     

Share This Page

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