Reduced power firing pin spring

Discussion in 'Modifications' started by Jacob W Plunkett, Aug 26, 2012.

  1. Jacob W Plunkett New Member

    Member Since:
    Aug 26, 2012
    Message Count:
    8
    Well i read around and couldnt find any writeups on dissasembly of the firing pin unit.

    well i figured it out. I ended up cutting about 3 coils off the factory sprong and cleaned and lubed everything up and man what a difference. trigger feels lighter not having to break from as much main spring tention and bolt runs easier.

    I havent even put one round down the pipe yet but i may tomorrow. but as a hand loader i did put a live primer in a resized case to ensure enough strength to set one off and it did well, 5 out of 5 with CCI primers (the hardest on the market)

    Jake,
  2. MechTech Moderator/ Damn Yankee

    Member Since:
    Aug 7, 2011
    Message Count:
    769
    Welcome to MossbergMVP.com Jake! Thanks for posting your modification. How did you remove your firing pin from the striker assy.?
  3. Jacob W Plunkett New Member

    Member Since:
    Aug 26, 2012
    Message Count:
    8
    Tighten up the firingpin tip gently in a vice and screw the aft portion of the assembly off CCW, the firing pin will thread off the front of the shaft (under the spring), be carefull (under spring tention) obviously, also note the small ring behind the firingpin tip is a smal washer with a recess. the recess goes forward towards the pin point.
  4. Jacob W Plunkett New Member

    Member Since:
    Aug 26, 2012
    Message Count:
    8
    it took be about 20 min and three blood blisters from pinches to figure it out. glad i didnt end up breaking anything as im sure parts arent easy to come by yet.

    this coupled with a reduced power spring and an aftermarket trigger would produce a stunning trigger pull im sure. im still using the factory junk trigger.

    JARD makes a replacement right?
  5. MechTech Moderator/ Damn Yankee

    Member Since:
    Aug 7, 2011
    Message Count:
    769
    Nice! I made this thread sticky and I will try to gets some pics or video together of the complete bolt disassembly this week. We really appreciate the info! That's pretty solid to have your first post be Sticky! Let us know how your MVP performs at the range. Any idea what your trigger weighs now?
  6. Jacob W Plunkett New Member

    Member Since:
    Aug 26, 2012
    Message Count:
    8
    i do not have a trigger scale handy but if i get a chance to get up to the local gun shop tomorrow before or after the range i will report back.
  7. MechTech Moderator/ Damn Yankee

    Member Since:
    Aug 7, 2011
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    769
    Either my factory trigger is really nice or I don't know what I am missing. I have had several M700 actions with trigger jobs and I will say the MVP is kinda gritty, but I still shoot tight groups, even off hand. I am gonna have to make a few of these mods and see the difference myself.
  8. YourMomma New Member

    Member Since:
    Aug 16, 2012
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    11
    Son of a B2#$@#!

    Now its time to find a similar spring that I can hack up.

    THANK YOU JACOB!
  9. bombadillo Moderator

    Member Since:
    Mar 19, 2012
    Message Count:
    546
    I'd love to see pics. Are you saying you cut coils off of the firing pin spring, or the trigger spring for the LBA trigger section. I'm thinking about cutting coils off of the trigger spring to lighten the trigger a bit. I haven't honestly done a lot on the trigger yet on here but have really been looking quite a bit on here to see what people are doing to play with them. Savage is easy to get parts from, but the mossbergs aren't so much yet.
  10. USMC6174 Member

    Member Since:
    Jul 24, 2012
    Message Count:
    93
    Gents,
    Sorry for the rookie question but jard inc makes a mossberg 4x4 trigger kit...is the drop in unit that everyone on the forum is using?
    -Steve
  11. Raydee38 New Member

    Member Since:
    Jul 7, 2013
    Message Count:
    5
    I am looking forward to pics on how to disassemble the firing pin spring. I got my Varmint model last week and had a chance to shoot it yesterday. I liked everything but the feel of the trigger, it seemed to take a good amount of force to get it to break. I thing the spring mod will do the trick.
  12. Lenard New Member

    Member Since:
    Mar 31, 2013
    Message Count:
    8
    I took mine apart and tried fitting a Remington 700 spring in the bolt and it is too big in diameter. I was hoping it would fit since I have a extra one sitting around.
  13. PapaBear New Member

    Member Since:
    Sep 10, 2012
    Message Count:
    20
    Still no pics or a write-up on this?

    Has anyone done this and documented it?
  14. rsbenden New Member

    Member Since:
    Jul 6, 2014
    Message Count:
    3
    I hated the 2 stage clunk,clunk bolt so I tried cutting coils from the bolt spring and it did the trick,after removing 2.5 coils I reassembled the bolt and applied moly graphite grease to the moving parts....she is smooth as can be now and my trigger pull also lost that gritty feel and now breaks crisp. I have owned enough guns with adjustable triggers to know this one is now sweet as hell n I wont be sniffin round those Jard triggers now. Im guessin round 3#. Jacob W Plunkett ~ thnx for the tip!
  15. bombadillo Moderator

    Member Since:
    Mar 19, 2012
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    546
    You gonna do a write-up on how you've done your trigger rsbenden?
  16. GrocMax Active Member

    Member Since:
    Jun 12, 2014
    Message Count:
    166
    Reducing firing pin spring preload/pressure and pin mass drastically is usually not a good idea. Its set where it is for a reason.

    BTW when you take coils off a spring you don't 'lighten' it, you actually give it a higher spring rate (shorten the torsion bar), but you do reduce the preload.
  17. MadMarty911 New Member

    Member Since:
    Jul 10, 2014
    Message Count:
    4
    For a sticky, it sure needs some pics or a better write up for those of us that arent familiar with trigger tune-ups! Hopefully soon because my trigger could stand to lose some weight. I havent told her outright but ive changed her diet to lighter grain pills lol

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