??how to disassemble the firing pin of a Nesika??

Discussion in 'Gun Project Questions & Gunsmithing' started by mao0720, Nov 8, 2019.

  1. mao0720

    mao0720 Silver $$ Contributor

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    Alright guys. I would like to to change the firing pin spring on my Nesika, but I cannot for the life of me find the right tool for the job. I have the kleindorst tool to remove the firing pin assembly from the bolt body, but what I need is a tool to compress the firing pin spring so that the cocking piece can be unscrewed from the firing pin. I do not believe I can use a Remington firing pin disassembly tool because the bolt shroud on the Nesika is closed at the back and therefore you can’t just push e firing pin out the back like you can on a Remington (I may be incorrect though). Does anyone have any suggestions on how to compress the spring on a Nesika action without injuring myself or my firing pin assembly? Thanks everyone for the help!
     
  2. centershot

    centershot Silver $$ Contributor

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    Remember that the bolt shroud is aluminum. At least it is on my TpE.
     
  3. Dusty Stevens

    Dusty Stevens COVFEFE- Thread Derail Crew Gold $$ Contributor

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    Should be 2 set screws (look with a bright light- dont stop until you know theres not another screw in there) in the cocking piece threaded down toward the firing pin. Remove those screws, and unscrew the pin from the cocking piece with shroud. I do this in a lathe for control but once it pops loose its not going to be violent. It only has about 1/2” of spring travel left but you do need to beware.
     
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  4. mao0720

    mao0720 Silver $$ Contributor

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    I have done this before and got it apart ok, but getting it back together was a PITA. Any suggestions there? I don't have a lathe to chuck it in, so that is not an option.
     
  5. Dusty Stevens

    Dusty Stevens COVFEFE- Thread Derail Crew Gold $$ Contributor

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    Drill a hole in a piece of wood of some type big enough the pin tip goes in but stops at the stop. You can push against that to screw it in.
     
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  6. Dusty Stevens

    Dusty Stevens COVFEFE- Thread Derail Crew Gold $$ Contributor

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    Mount that in a vise or even to the wall. The front edge of a wood table will work too.
     
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  7. carlsbad

    carlsbad Lions don't lose sleep over the opinions of sheep. Gold $$ Contributor

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    Measure and mark it well before you take it apart will help you get it adjusted properly when you reassemble. Lathe is a good control feature.
     
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  8. mao0720

    mao0720 Silver $$ Contributor

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    Right. I know firing pin protrusion has to be set correctly.
     
  9. Dusty Stevens

    Dusty Stevens COVFEFE- Thread Derail Crew Gold $$ Contributor

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    If i remember right it has a groove where the setscrews go like a bat. Youll put it back right by that. Protrusion is set by the shoulder on the pin
     
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  10. LRI_Chad Dixon

    LRI_Chad Dixon

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    A Nesika is a 105%, -5% type action. Simply to mean the striker is as cocked as its ever going to be when you raise the bolt handle. -That'll be relevant here in a sec...

    To tear down a Nesika fire control, 1st, remove TWO set screws stacked on top of each other down inside the tapped hole located in the cocking piece. A .0625" allen key is the size. Next, shine a light down in the hole. You should see a drill point that interrupts the threads machined on the back end of the striker pin. Take notice of how it looks.

    Now, unscrew the striker using an 11/32" or 8mm slim pattern type "ignition wrench" from Craftsman or wherever. When I do this I hold the shroud in my right hand with firm thumb pressure on the spring body. When it pops loose this will keep parts from shooting all over your blast radius.

    So, now do your thing. Whatever that might be.

    Reassembly. First, it sucks. Unless you have a fire control compression tool for assembly, it's just a bugger to do. I drilled a hole in the side of my bench large/deep enough to capture the front half of the striker collar. I palm to the shroud/cocking piece and place that just below my gut. Then lean in on it and deal with the thing trying to eat a hole through my hand. With the free hand, start turning clockwise to get the striker pin to engage the cocking piece. Use your mouth to tell anyone within a city block just how bad this part of the job sucks. :)

    Once it bites:

    I get a few revs deep, then I drop a .05" dia allen key into the hole where the two set screws go. I use my thumb to push down lightly as I screw it tight with the wrench. All I'm doing is "fishing" for the countersink that the set screws register into. Once I feel the little allen key fall into the pocket, I remove it and use a light to see down in there. It will time with another rev or so of rotation.

    Now, just stack your set screws and your done. To compress the assembly for re installation into the bolt there's two choices: A Kleinhorst tool from Brownells or a .05" allen key stuck into the rearmost hole and leveraged into the small hole drilled at the back of the bolt shroud. That is why those two holes are there. Grease up your shroud threads with either moly or copper anti seize.

    Nesika striker springs do not have a great deal of wall clearance from the inner bolt body ID. Use any lubrication very sparingly here. X10 if you use this thing in winter climates. It is worth your effort to find a lubricant that tolerates cold weather. If the stuff turns to peanut butter, you will have light strikes.


    I ran Nesika's rifle production from 2003 to 2006.

    Hope this helps.

    C.

    LRI
     
    Last edited: Dec 3, 2019
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  11. mao0720

    mao0720 Silver $$ Contributor

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    sooo helpful thank you. I knew you ran Nesika for a few years. Funny to hear that you just drill a hole in a bench too! Thanks for the info, Chad!
     
  12. LRI_Chad Dixon

    LRI_Chad Dixon

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    Your welcome.


    I neglected to add something at the end last night.

    The "105/-5" thing.

    The fastest way to kill a Nesika (any Nesika) action is to allow the bolt to "climb the ramps" during closure. It will work fine for a handful of times, then the bolt will roll an edge on the lug abutments right where they transition to the clearance ramps. When that happens it will work harden, then tear into itself and gall the dog snot out of the surfaces. It's a killer.

    So, when you get all this stuff together the very first thing you look at is the tab like feature of the cocking indicator sticking out the back of the bolt shroud. As you roll your bolt into battery you should see the tab move slightly FORWARD towards the muzzle. If it does this you are golden. If however you see the cocking indicator sitting stationary and the bolt shroud moving forward, STOP, STOP, STOP. You did it wrong and you'll kill that action in short order.

    What is happening is that the angled feature of the cocking piece is gaining purchase on the trigger's transfer bar PRIOR to the bolt lugs obtaining a flat purchase on the lug abutments of the receiver. The timing is "too advanced". You have to "retard" it slightly by unscrewing the striker pin slightly so that the cocking piece is basically moved rearward by a small amount. This is usually only an issue when installing a new pin that lacks the detent/countersink feature. Going too far the other way results in loss of striker pin travel. It'll be immediately evident because the first portion of the cocking stroke on the handle is basically cocking "air" as the cam feature becomes lazy to engage the nose of the cocking piece. This is when you end up with a 105, minus 15 or 20 or whatever.

    Make sense?

    The fire control timing on a Nesika is vital to its long term function. The window where it works properly is pretty narrow as the striker travel is also dependent upon how this all goes together.

    Last: Striker pin protrusion from the face of the bolt where the case head sits is (was, back then anyway) .05" to .052".


    Sorry I forgot this last night.

    C.
     
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  13. djporter

    djporter Silver $$ Contributor

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    Good stuff here, thank you
     
  14. Dusty Stevens

    Dusty Stevens COVFEFE- Thread Derail Crew Gold $$ Contributor

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    ^ this info is golden and should be read carefully by all the action retimers that want their rigs timed too perfect.
     
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  15. gstewart

    gstewart

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    I tried to contact Nesika and even Remington to get either replacement firing pin spring or specs for third party procurement to no avail.

    Model R (receiver lenght 7.36''). Help appreciated.
     

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