AR-15 malfunction
11-16-2018, 09:54 AM
#1
Spike
Thread Starter
Join Date: Nov 2018
Posts: 1
AR-15 malfunction
I own an Anderson AM-15. Whenever I fire, it extracts and ejects the spent case, then reloads a new round. However, the trigger doesn't seem to reset and I have to half pull the charging handle or smack the side or the rifle before i can shoot again. Then I have to repeat the prosess again
11-16-2018, 01:06 PM
#4
Typical Buck
Join Date: Apr 2017
Posts: 995
Sounds like it's not going into battery to me. Light spring? Maybe need to do a complete tear down and give your BCG a good scrub and lube? Pull your trigger group and give it a good cleaning while you are at it. And don't lay on the lube heavy on the trigger assembly. A light coat works fine and will attract and keep less gunk.
11-16-2018, 05:47 PM
#5
Nontypical Buck
Join Date: Apr 2015
Location: Germany/Calif.
Posts: 2,664
I'm far from a AR 15 expert, but at first blush it sounds like the bolt may not be going far enough back for the disconnector to catch the hammer. A few reasons for this, buffer spring too stiff (old sticky oil, trash or whatever), which is unlikely as they don't usually get stiffer with use. Might be a partial blockage of the gas tube. I had one that did what you describe, kind of. I eventually found a tiny piece of cleaning patch jammed in the barrel end of the gas tube. Anything from dirt or sticky oil on the bolt to a dirty chamber can slow the bolt, you may be in the sweet spot where the bolt is slowed just enough to not engage the disconnector and hammer hook (catch) but far enough to successfully eject the spent case.
Maybe your disconnector or hammer hooks aren't catching for some reason. Pretty easy to imprint the hooks, a very little yellow crayon (or lipstick) on one of the hooks then work the bolt and the trigger a few times and see how the dye smears, may take a few tries to get a good smear. You can see if they hook deep enough or hook all the way across the face of the hooks, in other words have a good fit. The disconnector and trigger hooks you can feel with your finger tip, maybe someone overdressed them for trigger smoothness pull and they aren't catching sometimes or one or the other of the hooks is rounded somehow.
When you said you have to partially pull the charging handle back and/or slap the side of the rifle to get the disconnector to catch kind of threw me. The disconnector isn't going to catch with a partial charge pull on the handle. Weak disconnector spring, the hammer really stiff on the pin (axis). and/or the disconnector really sticky rotating on the pin (axis).
My names for some of these items may be off, doing it and talking about it are two different things. Sounds complected it really isn't, not all that any parts in an AR 15.
Everybody has their own magic firearm lube. Mine are bore cleaner, liquid wrench 2 and Ether for cleaning and Break Free for lubrication, Old oil gets sticky and stiff either from the heat or age. It can get jelly like or even stiffer.
Maybe your disconnector or hammer hooks aren't catching for some reason. Pretty easy to imprint the hooks, a very little yellow crayon (or lipstick) on one of the hooks then work the bolt and the trigger a few times and see how the dye smears, may take a few tries to get a good smear. You can see if they hook deep enough or hook all the way across the face of the hooks, in other words have a good fit. The disconnector and trigger hooks you can feel with your finger tip, maybe someone overdressed them for trigger smoothness pull and they aren't catching sometimes or one or the other of the hooks is rounded somehow.
When you said you have to partially pull the charging handle back and/or slap the side of the rifle to get the disconnector to catch kind of threw me. The disconnector isn't going to catch with a partial charge pull on the handle. Weak disconnector spring, the hammer really stiff on the pin (axis). and/or the disconnector really sticky rotating on the pin (axis).
My names for some of these items may be off, doing it and talking about it are two different things. Sounds complected it really isn't, not all that any parts in an AR 15.
Everybody has their own magic firearm lube. Mine are bore cleaner, liquid wrench 2 and Ether for cleaning and Break Free for lubrication, Old oil gets sticky and stiff either from the heat or age. It can get jelly like or even stiffer.
11-16-2018, 10:11 PM
#7
Nontypical Buck
Join Date: Apr 2015
Location: Germany/Calif.
Posts: 2,664
I just know one thing for sure with a semi auto, no matter which lube you choose, you had better check the firing pin and make sure it isn't sticky from old thick oil, dirty oil or very cold oil.
Burnt powder residue and oil mix can get way thick and gummy. That is why I prefer aerosol cans so I can flush/blow out the really tight places.
I bought some refillable aerosol cans I can refill with whatever I'm using, cleaning or lube. I use dry argon or dry CO2 as a propellant (MIG gas). Out with the old and in with the new.
Last edited by MudderChuck; 11-16-2018 at 10:24 PM.
11-17-2018, 10:59 AM
#8
Nontypical Buck
Join Date: Oct 2013
Location: Marriottsville, Maryland
Posts: 1,058
Maybe the gas tube is not lined-up with the receiver correctly. Also...make sure the two gas key bolts on the bolt carrier are tight an staked in.
Do a AR check function with the gun unloaded an magazine not inserted --- Pull the charging handle back to cock it. Let the BCG (bolt carrier group) go into battery. Put the safety selector on safe --- Press the trigger back --- It should not let the hammer fall --- Put the safety in the off position and press the trigger --- The hammer should fall --- Keep your finger pressed back on the trigger and charge with the charging handle and let it go back into battery --- Slowly release the trigger while listening for the disconnector "click." You should hear the click --- if not --- it might be something wrong with the trigger group.
Do a AR check function with the gun unloaded an magazine not inserted --- Pull the charging handle back to cock it. Let the BCG (bolt carrier group) go into battery. Put the safety selector on safe --- Press the trigger back --- It should not let the hammer fall --- Put the safety in the off position and press the trigger --- The hammer should fall --- Keep your finger pressed back on the trigger and charge with the charging handle and let it go back into battery --- Slowly release the trigger while listening for the disconnector "click." You should hear the click --- if not --- it might be something wrong with the trigger group.
Last edited by Erno86; 11-17-2018 at 11:16 AM.
11-17-2018, 11:42 AM
#9
Nontypical Buck
Join Date: Oct 2009
Location: Kansas
Posts: 3,905
If the round is extracting and ejecting properly, and it's stripping the next round from the mag into the chamber, it isn't a gas issue.
If the trigger is failing to reset, AND the rifle isn't doubling when you release the trigger after a shot, AND it's ejecting and stripping the next round into the chamber:
1) Disconnector isn't catching the hammer. This would mean the trigger would simply be dead as if the rifle had been dry fired, because the hammer would follow the carrier back as it closed. The fact you need to half cock the charging handle is one troubleshooting clue for this. HOWEVER, whacking the rifle on the side would do absolutely nothing, so I'm doubtful this is the issue.
2) Disconnector isn't RELEASING the hammer to the trigger/sear. You SHOULD hear a distinctive "cluck" sound releasing the trigger after a shot, where the disconnector releases the hammer to the trigger/sear. If the disconnector isn't traveling freely or is over-length, it won't release. Sometimes a sharp "whack" to the side of the rifle would cause the disconnector to slip from the hammer, just as half cycling the action might cause enough jarring to release the hammer.
If the gas key were lose or gas tube misaligned, causing the carrier and bolt to fail to close into battery BUT allowing sufficient travel for ejection and reloading, the trigger would not be dead, as the hammer is cocked WAY earlier than cartridge ejection. The trigger would be live, the carrier would be visibly out of battery, and attempting to fire would drop the hammer on a "squishy carrier" or stuck carrier, where it wouldn't hit hard enough to ignite (it MIGHT fire), but would offer an audible hammer fall - dry fire click. The hammer can often jar the carrier/bolt the rest of the way into battery, forcing over a partial misalignment. Magazine feed lip drag would cause the same result - which isn't consistent with what you're describing.
Sounds like you simply have a tolerance stacking issue in the fire control group, and your disconnector is failing to release. Couple options there - replacing the disconnector the best of any option. Stoning a bit off of the disconnector to shorten it's claw is a second option. Peening the front tip of the disconnector, or adding a dawb of devcon steel under the tip to help the trigger push the disconnector off are a third option (1 & 2 are orders of magnitude better).
If the trigger is failing to reset, AND the rifle isn't doubling when you release the trigger after a shot, AND it's ejecting and stripping the next round into the chamber:
1) Disconnector isn't catching the hammer. This would mean the trigger would simply be dead as if the rifle had been dry fired, because the hammer would follow the carrier back as it closed. The fact you need to half cock the charging handle is one troubleshooting clue for this. HOWEVER, whacking the rifle on the side would do absolutely nothing, so I'm doubtful this is the issue.
2) Disconnector isn't RELEASING the hammer to the trigger/sear. You SHOULD hear a distinctive "cluck" sound releasing the trigger after a shot, where the disconnector releases the hammer to the trigger/sear. If the disconnector isn't traveling freely or is over-length, it won't release. Sometimes a sharp "whack" to the side of the rifle would cause the disconnector to slip from the hammer, just as half cycling the action might cause enough jarring to release the hammer.
If the gas key were lose or gas tube misaligned, causing the carrier and bolt to fail to close into battery BUT allowing sufficient travel for ejection and reloading, the trigger would not be dead, as the hammer is cocked WAY earlier than cartridge ejection. The trigger would be live, the carrier would be visibly out of battery, and attempting to fire would drop the hammer on a "squishy carrier" or stuck carrier, where it wouldn't hit hard enough to ignite (it MIGHT fire), but would offer an audible hammer fall - dry fire click. The hammer can often jar the carrier/bolt the rest of the way into battery, forcing over a partial misalignment. Magazine feed lip drag would cause the same result - which isn't consistent with what you're describing.
Sounds like you simply have a tolerance stacking issue in the fire control group, and your disconnector is failing to release. Couple options there - replacing the disconnector the best of any option. Stoning a bit off of the disconnector to shorten it's claw is a second option. Peening the front tip of the disconnector, or adding a dawb of devcon steel under the tip to help the trigger push the disconnector off are a third option (1 & 2 are orders of magnitude better).
