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 Lower causing trigger Problems??? (W/ Pics)
AMUshooter10  [Team Member]
12/12/2011 10:59:55 AM EST
I have a lower, new, and I put in the trigger group in and about every 20 cycles on the reset it will go off. No es bueno.

So I put a different trigger out of another gun and it won't go off on the reset but it sits in the lower weird and every once in a while I will pull the trigger and there will be a noticeable delay when it fires.

The lower is substantially fatter on the left side of the trigger group than on the right.

My question is; Could the lower be causing the trigger problems?

I sent the 1st trigger back for eval because I felt it was unsafe plus it had a pretty crappy pull. The trigger in now (pics are of that one) works but feels different than in the other lower.
Weird...




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j3_  [Team Member]
12/12/2011 1:25:27 PM EST
No idea about the type trigger you have but I did have a lower once that the trigger pin holes were .020 to far down off the top plane of the lower and it caused reset problems when the trigger was held to long after firing.
occasionalvisitor  [Member]
12/12/2011 1:39:05 PM EST
The thickness of the receiver sides doesn't have anything to do with the "doubling" problem that you had.

The upper photo (your first FCG?) shows a beat notched hammer. The hammer and/or disconnector are probably damaged or worn-out, and the cause of the problem. I would have purchased a new major name (I like PSA) LPK and replaced all of the lower receiver parts.

The second photo shows a trigger with a funny rear portion. Is that an aftermarket trigger of some sort, or a modification to a full-auto trigger (did you buy a surplus parts LPK?) to make it legal for use on a semi-auto firearm?

I'd say that you need to buy a new LPK and give up on the inexpensive/poor quality or surplus parts.
AMUshooter10  [Team Member]
12/12/2011 1:56:38 PM EST
Originally Posted By occasionalvisitor:
The thickness of the receiver sides doesn't have anything to do with the "doubling" problem that you had.

The upper photo (your first FCG?) shows a beat notched hammer. The hammer and/or disconnector are probably damaged or worn-out, and the cause of the problem. I would have purchased a new major name (I like PSA) LPK and replaced all of the lower receiver parts.

The second photo shows a trigger with a funny rear portion. Is that an aftermarket trigger of some sort, or a modification to a full-auto trigger (did you buy a surplus parts LPK?) to make it legal for use on a semi-auto firearm?

I'd say that you need to buy a new LPK and give up on the inexpensive/poor quality or surplus parts.


I assure you they are not poor quality parts. The LPK is from JPE and the the trigger is the same in both pictures BTW.

And the trigger in there now is fine in the lower it came out of. Like I said, it just acts up in this new lower.

Its not doubling with the 1st trigger group I sent back. It is firing on the reset if I hold it to the rear, pause, then let it reset it fires.

AMUshooter10  [Team Member]
12/12/2011 1:57:57 PM EST
Originally Posted By j3_:
No idea about the type trigger you have but I did have a lower once that the trigger pin holes were .020 to far down off the top plane of the lower and it caused reset problems when the trigger was held to long after firing.


This sounds like me. I will measure from the top down and compare. Thanks!
Dano523  [Moderator]
12/12/2011 3:19:48 PM EST
Pull the sector and see if the problem goes away.


If it does, then you will need to mod the flat on the selector to get the needed trigger pull distance for a clean hammer release.

If it does not, then check the other side of the trigger at the front to see if it's bottoming out against the bottom of the receiver cavity there.

As for doubling problem, if there is not enough trigger over travel after hammer release (at least a 1/16" needed), then the disco does not get a good grip on the hammer at rest, and what causes the problem.

Also clock the hammer back to the disco, then slowly release the trigger. The hammer should be release just about when the trigger almost comes to rest, not farther back then this (way before the trigger comes to rest). If the disco does release the hammer with about the trigger 1/2 to 1/4 on the way to home, it just dam easy to trigger dance the rifle and cause bursting by the op.
AMUshooter10  [Team Member]
12/12/2011 4:52:28 PM EST
Originally Posted By Dano523:
Pull the sector and see if the problem goes away.


If it does, then you will need to mod the flat on the selector to get the needed trigger pull distance for a clean hammer release.

If it does not, then check the other side of the trigger at the front to see if it's bottoming out against the bottom of the receiver cavity there.

As for doubling problem, if there is not enough trigger over travel after hammer release (at least a 1/16" needed), then the disco does not get a good grip on the hammer at rest, and what causes the problem.

Also clock the hammer back to the disco, then slowly release the trigger. The hammer should be release just about when the trigger almost comes to rest, not farther back then this (way before the trigger comes to rest). If the disco does release the hammer with about the trigger 1/2 to 1/4 on the way to home, it just dam easy to trigger dance the rifle and cause bursting by the op.


Ok, so I tried and tried but I can't get the new trigger to delay or hang fire again. So I will blame that incident on the cold weather with some CLP laying in the trigger GP.

I took out the selector and everything is as you say it should be. Maybe a little close on the over travel but I like that.

So the new lower works with two other triggers I have, just not the first one. But it is a wee bit thinner all around. My trigger pins stick out a little on the sides. Meh...

In conclusion we think it must just be the new trigger GP I got was bad? The trigger manufacturer should have it soon and I will let you guys know what they say.

Thanks



458winmag  [Team Member]
12/12/2011 7:25:19 PM EST
Originally Posted By AMUshooter10:
Originally Posted By Dano523:
Pull the sector and see if the problem goes away.


If it does, then you will need to mod the flat on the selector to get the needed trigger pull distance for a clean hammer release.

If it does not, then check the other side of the trigger at the front to see if it's bottoming out against the bottom of the receiver cavity there.

As for doubling problem, if there is not enough trigger over travel after hammer release (at least a 1/16" needed), then the disco does not get a good grip on the hammer at rest, and what causes the problem.

Also clock the hammer back to the disco, then slowly release the trigger. The hammer should be release just about when the trigger almost comes to rest, not farther back then this (way before the trigger comes to rest). If the disco does release the hammer with about the trigger 1/2 to 1/4 on the way to home, it just dam easy to trigger dance the rifle and cause bursting by the op.


Ok, so I tried and tried but I can't get the new trigger to delay or hang fire again. So I will blame that incident on the cold weather with some CLP laying in the trigger GP.

I took out the selector and everything is as you say it should be. Maybe a little close on the over travel but I like that.

So the new lower works with two other triggers I have, just not the first one. But it is a wee bit thinner all around. My trigger pins stick out a little on the sides. Meh...

In conclusion we think it must just be the new trigger GP I got was bad? The trigger manufacturer should have it soon and I will let you guys know what they say.

Thanks





So, who made this lower?
AMUshooter10  [Team Member]
12/13/2011 5:23:42 AM EST


[/quote]

So, who made this lower?[/quote]


The lower is good enough. Its not real important who made it. I think its just bad luck with the trigger parts.
458winmag  [Team Member]
12/13/2011 3:47:35 PM EST
Originally Posted By AMUshooter10:




So, who made this lower?[/quote]


The lower is good enough. Its not real important who made it. I think its just bad luck with the trigger parts.
[/quote]

Then why was it your heading for this post?
AMUshooter10  [Team Member]
12/13/2011 3:58:10 PM EST
[/quote]

Then why was it your heading for this post?[/quote]
.
.
.
.
.
Because I wasn't sure if it was then. Some guys helped out, I did some tinkering with what they told me. And voila the consensus is its the trigger.

AMUshooter10  [Team Member]
12/15/2011 11:58:15 AM EST
Update:
So the trigger is fine according to the manufacturer. The parts kits are good in other guns.

But they seem to think it is the lower. They said its not common but that it sounds like the lower is a wee bit out of spec somewhere.

So I think I will just live with the lower b/c it does work ok with a RRA trigger in it now. Just not great...

I think I will put this lower on a blaster and use a different one for the 3 gun build I am trying to complete. Just not worth sending it back in to me.

Thanks for the help again. (dano, J3)




Dano523  [Moderator]
12/15/2011 5:31:55 PM EST
Originally Posted By AMUshooter10:
Maybe a little close on the over travel but I like that.




Again, you can either take off a few thousands of an inch on the selector fire flat surface to allow for just a tad more over travel after hammer release, of you try a few different selectors to see if one of them give you the needed added amount of over travel after hammer release for a clean hammer release without having to smith it.

In adjustable triggers, you go 1/4 turn after you get a clean release of the hammer on the trigger pull for reliability on release. This is because the hammer.disco, and trigger has some sideways movement to them in the receiver/trigger, and if all work to the high sides of the pins, then without that needed extra little bit of trigger pull, the hammer is not going to release from the sear, even with the hardest of trigger pulls.

AR15fan  [Team Member]
12/20/2011 10:10:22 AM EST
Originally Posted By AMUshooter10:
I have a lower, new, and I put in the trigger group in and about every 20 cycles on the reset it will go off. No es bueno.

So I put a different trigger out of another gun and it won't go off on the reset but it sits in the lower weird and every once in a while I will pull the trigger and there will be a noticeable delay when it fires.

The lower is substantially fatter on the left side of the trigger group than on the right.

My question is; Could the lower be causing the trigger problems?

I sent the 1st trigger back for eval because I felt it was unsafe plus it had a pretty crappy pull. The trigger in now (pics are of that one) works but feels different than in the other lower.
Weird...

http://i40.photobucket.com/albums/e237/amushooter10/IMG_2553.jpg

http://i40.photobucket.com/albums/e237/amushooter10/IMG_2551.jpg


Pic looks like hammer pin holes were drilled at an angle
AMUshooter10  [Team Member]
12/21/2011 7:46:09 AM EST
Originally Posted By AR15fan:
Originally Posted By AMUshooter10:
I have a lower, new, and I put in the trigger group in and about every 20 cycles on the reset it will go off. No es bueno.

So I put a different trigger out of another gun and it won't go off on the reset but it sits in the lower weird and every once in a while I will pull the trigger and there will be a noticeable delay when it fires.

The lower is substantially fatter on the left side of the trigger group than on the right.

My question is; Could the lower be causing the trigger problems?

I sent the 1st trigger back for eval because I felt it was unsafe plus it had a pretty crappy pull. The trigger in now (pics are of that one) works but feels different than in the other lower.
Weird...

http://i40.photobucket.com/albums/e237/amushooter10/IMG_2553.jpg

http://i40.photobucket.com/albums/e237/amushooter10/IMG_2551.jpg


Pic looks like hammer pin holes were drilled at an angle


Could be. What's the best way to check that I will try measuring down from the top I guess.

I got the trigger back from the manufacturer and it seems to be working fine now. They gave me a new disco and trigger spring. So I am hoping that is all it was. (trigger) I hate to have to shell a lower. Or send it back.
Thanks AR15fan.

AMUshooter10  [Team Member]
12/21/2011 8:14:38 AM EST
Nearest I can measure there is a slight difference in the hammer pin holes. The left side hole is higher.
I checked it against a different lower and the numbers were the same on the trigger hole but off on the hammer pin hole.
I tried to take photos of it.

It is working so far with the replacement trigger so I will just make this a backup lower I guess. Meh.
Thanks for the help






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