[dav38spl]

i have an ar15 lower is olimpic arms, the upper i dont recall. i have two problems the slim firing and chambering/locking the bolt. I am using remington ammo, not reloaded. The bolt has been taken completely apart and cleaned. At first I was thinking I lost a spring on the firing pin. I looked it up and found that there isn't one. When I chamber the first round by it works right. When i shot the first round the secound and third may slim firing. But the brace jam up before the fourth round loads. Any ideal about this problem?
The secound problem is the bolt going completely forward and locking. If it doesn't slim fire the round, the bolt doen't go forward enough to lock. I have looked for ware points and only found one place. Front of the bolt, left of the gas tub.Any ideas?

 

[Maine04657]

First is it a slam fire or a bad trigger? Put two rounds in the mag fire the first and if it does as you say the second will fire as well make sure you only pull the trigger One time. If it fires both rounds open the rifle and see if the hammer is down or forward. If it is forward then you have a trigger issue. If not then buy a new firing pin. As for the bolt head not locking into place this to could have several causes. The first one being dirt/ grime. Is the gas tube inside the upper bent or damaged in any way?

 

[Jim K]

Maine04657, I am a bit confused by your response. If the second round fires, the bolt will open and cock the hammer.

One thing missing is a defnintiion of a "slam fire". It usually means the gun fires before the bolt locks (aka "out of battery fire"); that will almost always destroy the rifle.

Since that obviously didn't happen, it is more likely that the bolt actually locked and the hammer fell, firing the round. That can be caused either by a worked over trigger/sear mechanism or (rarely) by a nervous finger actually pulling the trigger again.

There are ways to test those conditions, but I would ask someone familiar with that rifle to look at the sears and check for wear or improper work.

Jim

 

[Helix_FR]

I agree with Jim. Sometimes the gun is doubling and its not related to the bolt but the hand off between the disconnector and the sear is out of tolerance. what you end up with is the gun firing when you pull the trigger and when you let off the trigger. Most people don't notice bc the gun is recoiling but what is happening is the trigger finger is letting off and the disconnect is dropping the hammer and the sear is not catching it. Easy test. with the gun empty, pull the lower off, cock the hammer manually while your pulling the trigger, let the disconnect catch it, then let off the trigger really slow. It should hand off to the trigger sear, in your case, it may drop the hammer. if it does, take it to someone that knows AR's really well. It may need a new disconnector or the engagement foot on the disconnect may need to be relieved.

 

[Maine04657]

Maine04657, I am a bit confused by your response. If the second round fires, the bolt will open and cock the hammer.

Me to? My brain and fingers where not working on the same plane.

Also keep in mind a firearm that discharges more then one round per trigger pull is a machine gun and CAN get you in trouble.

 

[jlloyd73]

I had the same issue with my AR15 when I first built it. It all boiled down to the disconnector.

 

[GunHugger]

I had the same issue with my AR15 when I first built it. It all boiled down to the disconnector.

Or the disconnector spring installed incorrectly.

Or shooter technique.

Not holding the gun somewhat firmly to the shoulder with a light finger on the trigger can cause the same result. Some people do it on purpose...some by accident without knowing it.

Here's how the trigger works.

 

[jlloyd73]

Nope....there was a defect in it. If you put that one side by side with another one it looked like the tip (hook) part of the disconnector was shaped different.

Changed that one little part and all was well. As a matter of fact it was the fine guys here on the site that helped me figure that problem out some years ago.

 

[goofy]

GunHugger
That is a great post I love the moving picture!!!!
This is a great way to show it.
Mike

 

[dav38spl]

i tried this last night. I took the bolt from my colt and got the same results on both isues. I put two rounds in the mag. I pulled the trigger and held it back and the gun still slam fired when it chambered correct. I have never had the trigger group out so i will start looking it over. I bought the gum from a pawn shop so i can say what was done to it. i have ouwed it for over 9 yrs never spent alot of time shooting it. The gun is very clean. I will keep working on it tell it is right. Thanks for all the advice