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1big4x
05-02-2011, 8:26 PM
I built 3 AR's on High Standard lowers with DPMS lower parts kits and took 1 to the range yesterday.Now to the problem.After firing a round and slowly resetting,it would fire 2-3 more rounds,after that it has a dead trigger.I changed uppers with a Colt 6940 and still had the problem.Everything looks good inside the lower compared to 3 other Colts.I haven't taken it all the way apart yet or called DPMS.Anyone else ever had this happen?

Librarian
05-02-2011, 8:29 PM
Take.

It.

Apart!!!

Until you treat it as broken, you have a functioning and illegal full-auto weapon.

Us3rName
05-02-2011, 8:32 PM
sounds like your trigger is bad. Check the sears. do not take it out anymore. hell - take it apart and inspect everything carefully. Check your trigger group and take pictures if you can. What you have now is considered ILLEGAL and is definitely not worth getting ****** over.

apbrian112
05-02-2011, 8:33 PM
Take the trigger group out of the lower immediately! You have inadvertently manufactured an automatic rifle.

Take it apart and reinstall the parts correctly, then perform a functions test (something you should do everytime you have your rifle apart and just good practice as part of your maintenence routine). We had to do this in the Army after cleaning our rifles, every darn time.

SixPointEight
05-02-2011, 8:36 PM
Is this not the standard disconnector spring being backwards? Take it apart. Put it together right. Do a dry fire function check(which you should have done in the first place, before ever putting a round through it) to make sure it's working right.

$P-Ritch$
05-02-2011, 8:36 PM
I'm not 100% on this, but couldn't this be a symptom of the disconnector spring being installed upside down?

The wider portion of the spring needs to go into the trigger first. Hopefully someone more knowledgeable will chime in.

Definitely take it apart ASAP.

Edit: looks like JT beat me by a few seconds, but at least that confirms my initial thoughts.

SixPointEight
05-02-2011, 8:40 PM
I'm not 100% on this, but couldn't this be a symptom of the disconnector spring being installed upside down?

The wider portion of the spring needs to go into the trigger first. Hopefully someone more knowledgeable will chime in.

Definitely take it apart ASAP.

Edit: looks like JT beat me by a few seconds, but at least that confirms my initial thoughts.

I pretty much guarantee it's this. It's possible there's an out of spec part, but more likely than not, it was the nut behind the wrench.

r6raff
05-02-2011, 8:43 PM
Yea, I agree with others that say check the disconnector spring. Always perform a functions check after building, rebuilding, replacing parts and cleaning. You would have seen this prior to going to the range and risking getting popped for a felony AW possession.

Ohh yea, like the others have said, take that upper off immediately, and check that disconnector spring

drunktank
05-02-2011, 8:45 PM
This thread shows a picture of how the disconnector spring should go in (bigger side down). Might have to twist a bit to seat it all the way in. I know u mentioned that you've already built two other lowers but hope this helps.

drunktank
05-02-2011, 8:45 PM
Oops here it is :0)

http://www.ar15.com/forums/topic.html?b=3&f=4&t=428705

Joe
05-02-2011, 8:45 PM
Ohh yea, like the others have said, take that upper off immediately, and check that disconnector spring

^^this

drunktank
05-02-2011, 8:47 PM
Ahh crap, not the link I meant (I'm not on my home computer sorry). The picture and comments do help though if you have a disconnector spring problem!

Cokebottle
05-02-2011, 8:48 PM
Is this not the standard disconnector spring being backwards? Take it apart. Put it together right. Do a dry fire function check(which you should have done in the first place, before ever putting a round through it) to make sure it's working right.
Usually is.

Installed upside down to be exact.

The disconnector spring has one end that is slightly larger. That end goes down into the trigger. It's a PITA, but it will fit.

And this thread needs to go away as soon as the OP gets the information he needs.

tuna quesadilla
05-02-2011, 8:48 PM
Okay, I'm gonna walk you through an AR-15 function check here.

1: Ensure the rifle is unloaded
2: Ensure the rifle is unloaded
3. Rack the charging handle.
4. Place safety on "Safe" and pull the trigger. The hammer SHOULD NOT fall.
5. Place safety on "Fire" and pull the trigger. The hammer SHOULD fall.
6. Keeping the trigger pulled to the rear (do not let go), rack the charging handle again. Sloooowly release the trigger. You should feel it click back into place and the hammer SHOULD NOT fall.
7. Pull the trigger. The hammer SHOULD fall.

Check your disconnector spring and perform this function test again. If your rifle makes it through the function test exactly the way it's supposed to, you're most likely good to go.

Josh3239
05-02-2011, 8:50 PM
This why you function test after builds. Don't know why people skip such an important step.

Rip out your disconnector spring and put it in the right way, then perform a function test. I'd put money down that that is the problem.

G38xOC
05-02-2011, 8:51 PM
Trigger Trigger Trigger .. it may looks same but mine was out of spec ( what stag said ) . I installed their new trigger and problem solved

Us3rName
05-02-2011, 8:52 PM
And this thread needs to go away as soon as the OP gets the information he needs.

agreed.

Grumpyoldretiredcop
05-02-2011, 8:53 PM
Assuming that the problem is an incorrectly installed disconnector spring, once you have made the repair, be sure that you operationally check the rifle as follows before taking it into public. If it fails op check, you may have a problem/problems that are beyond your ability to solve. Take the rifle to a qualified armorer or gunsmith.

Op check:

SAFE: Pull the charging handle to the rear and release. Place the selector on SAFE. Pull the trigger, and the hammer should not fall.

FIRE: Place the selector on FIRE. Pull the trigger and hold to the rear. The hammer should fall. Continue to hold the trigger to the rear, pull the charging handle to the rear, and release it. Release the trigger with a slow, smooth motion until the trigger is fully forward. The hammer should not fall. Pull the trigger. The hammer should fall.

tuna quesadilla types faster than I do!

NYY
05-02-2011, 9:01 PM
i have a high standard upper! no problems. haha. if that helps at all.. in any..possible way haha

goodlookin1
05-03-2011, 5:47 AM
- Trigger Spring might be upside down
- Disconnector spring might be missing
- Back of hammer might have been chipped off so as to not allow the disconnector to engage and hold
- Rounded over/chipped off trigger release point, either on the hammer and/or trigger
- Disconnector notch catch broken off
- Out of spec lower (unlikely)
- Illegal FA FCG parts (also unlikely unless intentional)

Guarantee it's one of those.

Army
05-03-2011, 6:56 AM
Also make sure the trigger spring was insatalled correctly. Upside down spring will not put any trigger pressure against the hammer notch.

Tacit Blue
05-03-2011, 2:03 PM
What type of bolt do you have AR15/M16? I doubt you got an A2 burst sear. Its more of an mechanical issue, verify all parts were installed correctly. Was this a homebuild or a rifle from a vendor?

MasterYong
05-03-2011, 3:29 PM
It amazes me that people post this stuff on public forums without the forethought to at least preface it with something like: "hey I might know this guy that might be having this problem..."

Oh, and your disconnector spring is upside-down. I might know a guy that might have once had that problem.

AR-15 Rep
05-03-2011, 4:08 PM
There could be multiple things going on, start with springs and proper installation, then hammer, disconnector, and trigger engagement, then out of spec lower. Have to do the process of elimination...

1big4x
05-03-2011, 9:26 PM
Disconnector spring was installed right,with the big end down towards the trigger.Function checked ok after build.Fired first 50 rounds ok.When I function checked it the first time I don't know if the trigger was trapped all the way to the rear.I think it was.When I check it now,with the trigger all the way back the hammer won't go under the disconnector.If I let the trigger go forward very very slightly it functions fine.I even tried putting the disconnector spring in up side down just to see if it made any differance,it didn't.Trigger and hammer springs both installed correctly.Disconnector moves up and down freely.I can change all parts 1 at a time with known good parts to see if that cures the problem.

1big4x
05-11-2011, 7:58 PM
Problem solved,hammer was bad.DPMS taking care of it by sending a new hammer and disconnector.

five.five-six
05-11-2011, 8:04 PM
there was this one time, this guy, he forgot to put that extra hook thingy in his hammer, and when you pulled the trigger, it just kept shooting until it ran out of boolits


the end

gatdammit
05-11-2011, 8:39 PM
Delete this thread....

rodeoflyer
07-05-2011, 3:33 PM
It amazes me that people post this stuff on public forums without the forethought to at least preface it with something like: "hey I might know this guy that might be having this problem..."

Oh, and your disconnector spring is upside-down. I might know a guy that might have once had that problem.

I know a guy who found his disconnector spring to be out of spec this weekend.

It was from a Stag lpk. The spring was installed correctly, but upon inspection and comparison with a DPMS spring - the Stag piece was about an eigth of an inch short.....