Help identifying this A2 action rifle

Discussion in 'Sako Medium Actions' started by London Limey, Jan 9, 2020.

  1. London Limey

    London Limey Member

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    Hi All,

    I have had this rifle in my possession for a number of years. I purchased it in the late 90's, as a wooden stocked A2 forester, stainless steel barreled 6PPC USA .

    It has lived in a synthetic stock since then, and has delivered outstanding performance with home loads in both PPC USA and adapted 220 Russian cases.

    I decided recently to do some work on the trigger, as newer rifles I have have now gotten me used to a lighter trigger. I stripped the group down with the aid of a bit of heat - it had been locktited together pretty well - and examined it. the unusual thing is, it does not seem to conform with any of the other trigger groups that I have found information on so far.


    In the pictures, you can see that at the top of the group, a spare - or what looks to be - take-up screw has been added in an open threaded hole. This serves no other purpose other than to act as a spare to me. The forward tensioning screw for the whole group is also at an angle. This too seems to be different from the other triggers I have found information on.

    from the serial number 33**33 , I would age it between 1977 -82, so I would say that it is not an original factory 6PPC , as the action is too old. Possibly originally a .243 ?
    The tension and backlash grub screws are also slightly different to each other. I found that out when they were removed and transposed, resulting in a much better feel to the adjustment of the trigger itself.

    If anyone can cast any light onto this rifles heritage, I would be most grateful.

    All the best. 20200108_143550[1].jpg 20200108_143550[1].jpg 20200108_143604[1].jpg 20200108_143617[1].jpg 20200108_143700[1].jpg 20200108_210206~2[1].jpg
     

  2. kirkbridgershooters

    kirkbridgershooters Well-Known Member

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    Your question is not entirely clear, but I will at least tell you what the adjustment screws are on the trigger.

    The trigger I have photographed has 3 screws, with 1 being the screw with a spring underneath, that adjusts the trigger pull.

    #2 is the overtravel screw which will limit the trigger once it has been pulled, to not have unnecessary travel.

    #3 is the screw that puts pressure of the whole trigger group against the bottom of the action.

    I am not sure of your reference to which screw hole and spare screw...

    5273538C-5B26-43E1-911C-B5BFE943ECFA.jpeg
     
  3. London Limey

    London Limey Member

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    Hi,
    Thank you for getting back so quickly.
    Thanks for confirming what screws #1,#2 and #3 are for. The 'spare' grub screws location is shown in the picture below.
    20200108_143759~2[1].jpg
    It is a nippled screw - small protrusion on the load bearing end - the same as the take-up screws.
    The hole that it is located in, is open - and the screw can be wound all the way through that casting. If it was there to stop the jam nut on the tensioning spring adjuster from coming undone, I thought it may have been longer and of a flat based type. Although, the screw that is in there is not long enough to act as a locking screw in that way.

    Just to recap. The original question was, " has anyone seen a trigger group with this grub screw in the top before, and what do you think this rifle was originally, if it was not a PPC when it left the factory?"

    New to this, so apologies. Can I ask what era rifle the trigger group you have posted comes from?

    Thanks in advance.
     
  4. kirkbridgershooters

    kirkbridgershooters Well-Known Member

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    I’m sure it didn’t leave the factory as a PPC. I have 4 PPC’s 2 sporter and 2 single shot and they are all short actions.

    There is also about .025” difference in the diameter of the bolt face as the PPC cartridge is that much smaller than the standard chambering which would most likely be 243, 308, 22-250 etc.

    I would look to see if the PPC case fits the bolt face perfectly and then check the bolt to see if it is serial numbered to the action.

    What era my trigger is, is unknown to me as I got it as a trigger to have as a spare. My trigger also has the same screw hole and screw in it. How many others have it, I wouldn’t know as this is the only trigger I have examined out of the action...
     
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  5. kevinlg

    kevinlg Well-Known Member

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    The small screw, on top of the trigger housing, is NOT a "spare"......on this, the standard #4 Sako sporter trigger assembly.

    This screw adjusts the alignment of the bolt sear to the trigger housing sear. It is usually adjusted such that the top of the trigger housing is approximately parallel to the bottom of the action.

    A trigger housing adjustment that is too "high" may not allow the bolt sear to move forward upon trigger pull. A too "low" adjustment may not allow the bolt sear to properly cock upon bolt closure.

    Note that it is only adjusted when the trigger is "off" of the action.

    Hope this helps.
     
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  6. paulsonconstruction

    paulsonconstruction Sako-addicted

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    Your trigger is the standard Sako #4 trigger used from 1959 to 1990 & as Kevinig mentioned the screw in the top is for setting sear engagement. Not all Sako #4 triggers had that screw, but either way the sear engagement was set at the factory & I highly recommend you not mess with it. If not set properly, which has already been done at the factory, the sear may not catch the cocking piece on closing & a slam fire can occur. That trigger is not designed to go below around 2 to 2.5 pounds safely. To do so will make your safety not function properly. Disassembling triggers without an understanding of how they function & are designed is a recipe for disaster. Please be careful!!
     
    Last edited: Jan 10, 2020
  7. tripledeuce

    tripledeuce Well-Known Member

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    The #4 trigger is attached to the bottom of the receiver by a pivot pin. The #3 screw and the " spare " screw are adjusting screws to set alignment of the sears which is factory set. Your #4 trigger appears to be missing the #3 screw.
     
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  8. stonecreek

    stonecreek SCC Secretary Forum Owner SCC Board Member

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    The Sako "#4" trigger came in several different configurations. I have only seen the one with the sear engagement adjusting screw on the top of the trigger on very early rifles. This leads me to believe that your rifle's trigger was replaced with an earlier one at some point in the past.

    As kevinlg points out, the screw, and thus the sear engagement can only be adjusted with the trigger dismounted from the frame. This means that adjusting the sear engagement is a process of trial and error -- a process not to be lightly undertaken if you are not very familiar with triggers and sear engagement.

    I'm assuming that you have the mounting screw (the one pointed mostly upward at the forward end of the trigger housing and labelled "3" in Kirk's photo. This screw should always be fully tight and the lock nut tightened down when the trigger is properly mounted. I've come across Sakos on which some genius tried to adjust the weight of pull by loosening this screw. AAARGH!
     
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  9. paulsonconstruction

    paulsonconstruction Sako-addicted

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    Screw #3 is NOT an adjustment screw. It is what holds the trigger group to the action and should be fully tightened with the lock nut secure.
     
  10. London Limey

    London Limey Member

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    Thanks triple. The #3 screw had been replaced with a cap head - shortened and honed to engage on the shoulder of the head, rather than have the lock nut adjustment. Someone has obviously spent a bit of time and effort tuning this group to what they wanted.
    I can see that setting the #3 screw is pretty important.
    And thanks to Kevin for explaining what the alignment screw does. It's suddenly as plain as day when someone tells you how it works.
    I have then set the top of the trigger assembly parallel to the bottom of the action using feeler gauges. The modification - not by me - to the #3 screw, when full engaged up to the shoulder of the cap head, enables you to set that adjustment screw pretty accurately. All be it you have to remove the trigger to do it............as said, trial and error.

    This is how it looks now.
    trigger.jpg
    The screws without lock nuts have been sealed in place with a dot of varnish.

    The bolt face is oversized for a PPC case head. So, I think its the original bolt. The serial number supports this anyway.

    Thank you all for your input and help.
    This rifle is certainly a mixed bag of fish ! The next investigation will be the barrel after testing that it still shoots okay.
     
  11. kevinlg

    kevinlg Well-Known Member

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    London,

    A couple of things......

    Since you've properly set the top "leveling" screw, the large front anchoring screw's position will change. The standard Sako set-up is a 6mmX1 slotted screw with lock nut.......that allows for slight rear leveling screw changes.
    A new screw can easily be made, and lock nut added. (note:a bit of caution.....when tightening, or loosening this slotted screw......be sure the nut is at the top of the screw to prevent splitting of the screw "slot" under screwdriver blade pressure.

    Also, the bottom trigger over-travel screw normally does not have a lock nut, from the factory. If you look closely, there should be a slight "stake" mark next to the threaded hole in the housing. When properly adjusted, the housing stake should be fairly tight on the screw threads. Even so......I usually "set" it's adjustment with a drop or two of clear fingernail polish.

    Hope this helps.......a bit more.
     
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  12. London Limey

    London Limey Member

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    Thanks Kevin,

    Yes it does. the addition of the nut to the over travel screw may have been a step too far.......I just happened to have some 4mm nuts that fitted both adjustment point screws ,without interfering with each other.
    After looking very carefully at how the sear engagement was affected by the adjustment screw, I could see how the fixing of the #3 screw length - by changing it to a screw that has a fixed datum, i.e. the shoulder of the cap head - once you had established the correct amount of protrusion of the trigger sear. This evidently had been done for me, by a previous owner, as adjustment of the small leveller screw was now a fine tuning rather than a full on stab in the dark.
    It was still quite interesting to see how much difference just a couple of turns on that screw - in or out - had on the engagement (or lack of !!) on the bolt sear.

    I should add at this point that I have worked as an engineer and craftsperson for nearly all of my working life. I do feel very comfortable stripping things like this down, and reassembling them. But it should act as a word of warning that if the correct questions are not asked when needed, some serious mistakes could happen.
    As this is my first venture into your forum, I would like to thank all that have been involved with their constructive input and help.
    I most certainly have benifited from the conversations, and hopefully we have all discussed something that will be of use to others in the future.

    Regards
     

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