Ar doubling

**Pukindog** · January 1st, 2008, 05:25 PM

I was shooting my Colt H-Bar the other day. First thing i noticed wrong was that the second round was being feed into the chamber but the rifle was not being cocked. Didn't happen all the time. Changed mags and the same thing happened. Then the fun started, the rifle started to double on me. Not every time.
Rifle has a Jewel trigger and about 4500 rounds through it. Was wondering if the sear/disconnector is going on it. I am going to take it over to a buddy of mine who is the armorer for a local police dept. Just looking for some thoughts from some AR mavins.

Jeff

**TonyF** · January 1st, 2008, 05:53 PM

The jewel trigger would be the first place to start. Do you still have the OEM FCG? Put them back in and see if the rifle still malfs.

**Pukindog** · January 1st, 2008, 05:56 PM

TonyF,

Nope, sold the parts when I replaced the trigger.

Jeff

**Lycanthrope** · January 1st, 2008, 06:19 PM

Just adjust the sear engagement on the Jewell. Or up the poundage a bit.

Going too light on the second stage will cause them to double. Your spring have likely lost some poundage and you need to readjust the trigger.

Lycannothardtoadjustthrope

**PA Rifleman** · January 1st, 2008, 11:26 PM

Something else to check:

Take a look at some of the rounds you've cycled through without firing. If there's a deep firing pin mark, the primers might be too soft. When the bolt closes, the firing pin drifts forward and sometimes sets the round off. U.S. military rifles require harder primers for safe operation.

A safer way you might be able to check for this is firing several different brands of ammunition. If some brands don't double, check primers. If it doubles no matter what type of ammo, have a look in your fire control group (FCG).

**Pukindog** · January 2nd, 2008, 02:15 AM

PA Rifleman,

These are the same rounds I have used for the last 4000 rounds. No problems until now. Tried the ammo for fun in my brothers' rifle ( same exact model ) and there were no problems. Don't think it is the ammo. Lycanthrope may be on the right track with the trigger/sear/disconect thing.
Jeff

**Lycanthrope** · January 2nd, 2008, 02:18 AM

Well I do have a couple Jewells on my AR's...........

Lycanhighlyadjustabletriggerthrope

**PA Rifleman** · January 2nd, 2008, 02:24 AM

Originally Posted by Pukindog

PA Rifleman,... Lycanthrope may be on the right track with the trigger/sear/disconect thing.
Jeff

Sounds like it. Good luck.

**Pa. Patriot** · January 2nd, 2008, 02:36 AM

Most likely disconnecter/sear engagement. Could be out of or not correctly adjusted fro installation (threshold).

Could also be affected by foreign matter like a blown primeror other debris. Yes, I've actually seen this, more than once