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AR 15 minute trigger job

Discussion in 'Rifle Country' started by wishin, Dec 2, 2009.

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  1. wishin

    wishin Member

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    I want to share my experience with the "15 minute trigger job" that's being touted on the internet as an inexpensive, but effective way to lighten the pull on your AR. Part of it involves cutting one of the legs of the hammer spring. Technically, it does reduce the pressure or force on the sear and hammer, but it also reduces the stored energy required to fire off the primer. After firing almost 80 rounds from my DPMS 6.8SPC, I'm more than convinced that the occasionally misfire I get is from the reduced force. Most showed a respectable indentation, however when the dent was so slight that it was obviously a light strike, it was my wake-up call.

    Before anyone looking to snipe and criticize me jumps in, let me admit that was a dumb-assed thing to do. The good news is a new spring costs only $1.50! Thought I'd save others the trouble of finding out for themselves.:cuss:
     
  2. Z-Michigan

    Z-Michigan Member

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    Interesting. Hadn't heard of this "technique" before.

    I have a 20-second trigger job. I apply NLGI #1 grease to the trigger/hammer mating surfaces. It's not magic, but it is an improvement, with no reliability issues.
     
  3. Walkalong

    Walkalong Moderator

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    I've heard of it, but would be more prone to try a reduced power spring before cutting one leg off the stock spring. Another cheap try.
     
  4. highorder

    highorder Member

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    Send your trigger group to Bill Springfield, and let him work on it for you.

    Cheap, fast, and great results.

    http://www.triggerwork.net/ar15s.html

    He does my AR's , and did a great job on my 10/22.
     
  5. wishin

    wishin Member

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    I did lightly hand hone the contact surfaces with a very fine stone and applied a small amount of lubriplate.

    Nevertheless, my tombstone may well read: The hardest part of getting your head out of your ass is getting past your ears!
     
  6. carbine85

    carbine85 Member

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    The 15 minute job was formulated for the 5.56. I have done this on two rifles but used a different spring from Brownell's. It works without failure but it doesn't replace a 2 stage or proper trigger job.
     
  7. wishin

    wishin Member

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    I've also wondered if perhaps different gunmakers use different sources/suppliers for springs, making some springs stiffer than others and thus more, or less, susceptible to this mod.
     
  8. Shung

    Shung Member

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    I did it on 3 of my 6 5.56 Ar's works like a charm, and it is very efficient.. I think the key here is that you are not using it on a 5.56 ammo.
     
  9. wishin

    wishin Member

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    I do believe you're right!
     
  10. Dr. Tad Hussein Winslow

    Dr. Tad Hussein Winslow member

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    Thank you for the heads up. Im my experience, the less you screw with the functional parts of a firearm the better. Generally speaking, you're better selling and getting exactly what you want from the factory if it exists.
     
  11. wishin

    wishin Member

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    I had the good fortune to attend an armorer's course in 1959, so have no compunctions about getting in over my head.:)
     
  12. JDGray

    JDGray Member

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    I've taken a little off the factory spring by unbending it at the coil, never tried cutting off a leg. The good thing is you can put more bend back into the spring, not so with cutting it.:)

    Another +1 for Bill Springfield's trigger work!
     
  13. Tirod

    Tirod Member

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    It has nothing to do with the caliber. The most common cartridges for the 6.8 are Silver State, which uses a harder primer than Fudd ammo. What size the bullet measures in a dial caliper can't affect it at all.

    I have been researching this mod and still can't justify reducing spring power for the sake of a marginally lighter trigger pull. Most shooters and their rifles aren't good enough - sorry - and can't point to a consistent improvement in scoring.

    It's race car engineering that doesn't deliver on the street.
     
  14. 250-3000

    250-3000 Member

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    I did the 15 minute trigger job about 600 rounds ago, modified replacement springs in case I screwed it up. No problems yet. Getting a Bushmaster 450 upper for Christmas, curious to see how the modified trigger spring maintains sear engagement under the heavier recoil..
     
  15. Dr. Tad Hussein Winslow

    Dr. Tad Hussein Winslow member

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    That made me laugh - thank you. And thanks for pointing out that it ain't got nuttin to do with chambering.
     
  16. Juice Boxes

    Juice Boxes Member

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    I may be wrong but i thought this was no good due to the fact AR triggers are case hardened and it would take the temper out of the steel.
     
  17. Tirod

    Tirod Member

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    Glad you laughed, I definitely put a lot of spin on that statement.

    I went back and looked at even more on this modification. First - it's a range competition trick, not for combat. Milspec ammo has a harder primer that won't always work with it. Civilian ammo with soft primers isn't affected, apparently. Hence my "Fudd ammo" comment. So, technically, when someone said 5.56 - milspec implied - I was a bit off.

    Because the hammer and sear are case hardened, the carbon content of the surface material is much higher than the soft core. It actually doesn't affect the temper at all - it's not a part with sufficient carbon content to "harden" and heat treat, like a knife blade. The carbon is actually allowed to diffuse in from an external source.

    The basic problem I have is that proponents of most trigger improvements aren't saying "NOT FOR COMBAT USE." I would include home defense and even hunting. Trunk guns or in vehicle mounts, same thing. Milspec triggers have the pull weight they do because of rough use and team members in close proximity.

    But once you start trimming springs, you're on your own. You are now writing your TDP specs. It can be a rude awakening.

    For those who keep researching, there are other methods out there that work and make sense, are less prone to screwing up, and don't cost money. I'm just not for this one.
     
  18. wishin

    wishin Member

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    I beg to differ on this generalization. We're not talking hair trigger, but maybe 4 lbs. Even a novice shooter can better appreciate the squeeze needed to reduce flinch by not having to press the trigger so hard as to then jerk it.
     
  19. Tirod

    Tirod Member

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    What is the purpose of the Colt Technical Data Package and it's adherence to military specification? To meet standards dictated by DOD that specify a trigger pull and a price. Milspec isn't 4 pounds. It's already been determined unsafe for use.

    I'm not saying I'm a big fan of hard, gritty triggers with miles of creep. But nobody has to jerk a trigger when taught properly to shoot the M16 to the 2 MOA spec and standard. Further, the M16 is probably the least likely military weapon to induce flinch. If anything, it's the cure for it. Uncle Sam trains tens of thousands of novices a year, flinching and jerking are fantasy arguments.

    I'm not saying a competent range shooter can't take advantage of it - but sincerely, a novice won't notice the difference until pointed out, and again - they can't shoot to the difference for a long time. It takes more than a few trips to the range a year to get there.

    Shooters who know enough to want a light weight trigger should also know why it may not be a good choice. Unintended consequences can and do occur.
     
  20. wishin

    wishin Member

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    If you think a 4 lb. trigger pull is unsafe, your arms probably hang past your knees. :)
     
  21. madcratebuilder

    madcratebuilder Member

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    That pushed coffee out my nose! pretty funny.

    If you shoot match competition you are limited to a minimum of a 4.5lb trigger. I shoot for 4.5-5lbs on all my mil-spec rifles. Ideally you have 3.5lbs on the first stage and break at 4.5lbs. That way your finger feels it as a 1lb trigger.
     
  22. wishin

    wishin Member

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    Now that's a great signature! Thanks for your service.
     
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