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AR-15 function issue

ammo guyammo guy Member Posts: 810 ✭✭✭

Having an issue with my AR, seems the bolt is not coming back far enough to cock the hammer, Usually ejects OK and picks up the next rd in the mag, but does not cock the hammer. Tried to shorten the recoil spring thinking this would help, no luck. I recall the last time I fired the rifle it was OK. Help would be appreciated.

Comments

  • NeoBlackdogNeoBlackdog Member Posts: 16,566 ✭✭✭✭

    Check to see if the disconnector is grabbing the hammer when it comes back.

    https://www.youtube.com/watch?v=wAqE-KLbiYc

  • MobuckMobuck Member Posts: 13,733 ✭✭✭✭

    Now, you'll need to replace the spring. DO NOT shorten that spring.

    Load one round and fire it with the empty magazine in place. If the bolt locks open properly, the bolt is cycling fully. Load one round and fire it w/o a magazine in place. If you can return the selector to the safe position, the hammer has reset and is caught by the sear. If you can't return the selector to the safe position, the disconnector isn't functioning properly and you need to find out why.

    The internals will not/should not allow the bolt to travel far enough to eject and pick up another round w/o re-cocking the hammer.

  • ammo guyammo guy Member Posts: 810 ✭✭✭

    Thanks so far, I can manually pull the bolt to the rear and the hammer cocks correctly. I have looked at the internal parts and can't see any issue there. I will try the suggested things and see how it goes.

  • MobuckMobuck Member Posts: 13,733 ✭✭✭✭

    By any chance have you had the FCG out/apart lately? It's a very common error to install the disconnector spring upside down. Try hand cycling the action with safety off and the trigger held back(as would happen with real firing).

  • bpostbpost Member Posts: 32,664 ✭✭✭✭

    Buy a new spring, check the buffer for signs of binding. The bolt being held open is not the same as the disconnector engaging. Open the rifle, cock the hammer and hold your thumb against it as you pull the trigger. Let the hammer go forward easy and KEEP THE TRIGGER PULLED TO THE REAR. Now push the hammer back down and see if it clicksand locks into place. As you let the trigger out the hammer should move to the sear releasing the disconnector. Let us know how that works.

  • ammo guyammo guy Member Posts: 810 ✭✭✭

    OK, did as suggested above, The hammer did not connect to the sear until I let the trigger go forward?

  • bpostbpost Member Posts: 32,664 ✭✭✭✭

    I am starting to think yo have an ammo issue, try a different brand of 5.56 NOT .223, they are loaded to different pressures. I still suspect an issue with your buffer but try the ammo first after you replace the spring. You may also have gas seal rings on the bolt worn out or a misalignment issue with the gas tube and bolt gas block. Make sure the bolt carrier gas block is tight and staked in place. How many rounds has this rifle seen?

  • ammo guyammo guy Member Posts: 810 ✭✭✭

    Checked the gas rings and they are OK, fired several types of ammo with no change in the situation. I don't think the gun has had more than 2-300 rds fired. As noted in the original question I have shot the gun before and did not have this issue. Have ordered new springs and will see if this does anything.

  • ammo guyammo guy Member Posts: 810 ✭✭✭

    Problem solved, found out that the small sear spring was missing, Replaced and seems correct now, thanks for all the replies.

  • MobuckMobuck Member Posts: 13,733 ✭✭✭✭

    "Problem solved, found out that the small sear spring was missing, Replaced and seems correct now, thanks for all the replies."

    Do you mean the "disconnector" spring???

  • MobuckMobuck Member Posts: 13,733 ✭✭✭✭

    "he bolt being held open is not the same as the disconnector engaging."


    That is correct BUT The OP suggests a question of BOLT TRAVEL/CYCLING "seems the bolt is not coming back far enough to cock the hammer".

    My suggestion is the correct answer for this question.

    The hammer is "cocked" well before the bolt cycles fully meaning that a full cycle of the bolt moves the hammer to a point PAST which the

    dsconnector is supposed to catch the hammer.

This discussion has been closed.