At the range with a new AR that is not feeding- help

Status
Not open for further replies.
M

mookiie

Member
Joined
Sep 16, 2010
Messages
653
Location
Delaware
i have an AR that is not feeding correctly. does not seem to have enough energy to eject and chamber. bullets work fine in another ar so i am not sure if it is a tight chamber problem or what? help please!


Posted from Thehighroad.org App for Android
 
Plugged or weak gas system/lack of lube. Can of carbon blaster or gun scrubber and bow out the gas tube. The other is check the three washers in the bolt. Be sure the slots are not ligned. They should be staggered. Also be sure there is light coat of oil where the bolt carrier slides in the reciever.
 
Check your gas key and make sure it is tight.
Check your gas rings and make sure they're all there and staggered.
Oil the gun well.
Try it again.
 
If all the above fail, check for leaks around the gas block, check that the gas tube is not damaged, and last make sure they drilled the barrel port the correct size for your barrel length -- should be 0.625 for a 16" 5.56 carbine.
 
mookiie said:
i have an AR that is not feeding correctly. does not seem to have enough energy to eject and chamber. bullets work fine in another ar so i am not sure if it is a tight chamber problem or what? help please!


Posted from Thehighroad.org App for Android
Click to expand...

Exactly what kind of failure(s) is it experiencing?

A failure to feed and a failure to eject are two different things.

What rifle (manufacturer, gas system, buffer weight, etc)? What ammo? What magazines? How much lube is on the bolt carrier group?

Is it a new rifle, or has it worked before? If it worked before, what ammo and mags?
 
If rifle is new, lube well and try full power ammo. Some of the cheaper stuff is loaded a little light, esp if .556 chamber and using .223 ammo.
 
Can a expert positively say if the gas rings need to be aligned or not? I keep hearing both stated as fact. I'm in the "it doesn't matter corner
 
DID YOU TRY MORE THAN ONE MAGAZINE ?

During my 30+ years of military and police service most failures to feed were due to a bad mag or one which was incompatible with that particular rifle.

BTW, was it a commercially made rifle or a parts gun ???
New or used ? Was it working before ? Full Length or carbine ?
 
Gas rings DO NOT need to be aligned, that is an old myth. The rifle should be able to function with just one gas key remaining. They should be tight though, to test this take the complete BCG, with the bolt extended, and place it bolt down on a table. The gas rings should be tight enough to keep the bolt carrier from sliding down on the bolt.

Also, what brand is the AR?
 
Armorer, US Army in the 90's

I have had this conversation before.

Page 3-42 of tm 9-1005-249-10

And

Page 2-30 of tm 9-1005-249-243&p

Stagger the gosh-darn rings.

Till I see a better reference, I consider this settled.
 
LIKE id SHOOTING SAID..

ARMY TM-9-1005-249-10

3-9. REASSEMBLY OF M16/M16A1 RIFLE (CONT).
BOLT CARRIER ASSEMBLY AND CHARGING HANDLE ASSEMBLY (CONT

4 Stagger gaps in bolt rings (5) to stop gas
loss.

AND... on page 3-10

TROUBLESHOOTING (CONT)
MALFUNCTION TEST OR INSPECTION CORRECTIVE ACTION

8. WEAPON HAS SHORT RECOIL.

Step 1. Gaps in bolt rings (not staggered).
Stagger ring gaps (p 3-42).

Step 2. Carbon or dirt in key and carrier assembly or on outside of gas tube.
Clean (p 3-34 and 3-30).

9. BOLT FAILS TO LOCK AFTER LAST ROUND.
Step 1. Check for dirty or corroded bolt catch.
Clean (p 3-38).
Step 2. Check for faulty cartridge magazine.
Replace (app B).

10, SELECTOR LEVER BINDS.
Check for not enough lubrication on selector lever (l).
Lubricate with CLP (item 1,


For those who were not issued a copy....

http://pdf.textfiles.com/manuals/MILITARY/united _states_army_tm_9-1005-249-10 - 11_may_1990.pdf
 
By the By,,,
When one of my old units was issued 120 brand new FN made M16A2 rifles,,,, they were all so tight that none of them would function. ( plus they had a weird smell like some sort of smoke when you hand-cycled the actions)

We oiled the heck out of them and took a flat bed truck of ammo out to the range. Then I had everyone shoot until they could not see straight... Mostly single shot because the guns were not working, even with a couple of us running up and down the line with a giant janitor spray bottles of lube oil...

We ended up taking a big rotary brush to the inside of the upper receiver on about 30 rifles... Plus we had to replace the supposedly new bolt gas rings on about half the rifles..

Later when they issued us M-4s, the problem was not nearly as bad.. Although almost none of the new magazines that came with the M-4s worked...
 
Wow thanks for all the replies! Let me see if I can answer your questions. The lower was assembled by myself, geissle trigger, ATI polymer lower and PSA lower parts kit. I had two AR's with me at the range. One a Stag Arms Model 3 and the other the malfunctioning AR. I switched the lowers and the malfunction still occurred. I put the assembled lower on the stag arms upper and it worked flawlessly. The other upper is a R-guns upper that was brand new unfired. I put the Rguns upper on the stage lower and still had issues. I was able to get the AR functioning, I believe that it is a problem related to the magazines. I believe the bolt is rubbing against the lip of the mags on one side. I could see dome Material shaved off of some of the pmags I was using. I also saw similar wear marks on the metal magazine I tried. It may be related to the ammo because it is handloads that are loaded mild. I am going to try to dremel the lip of the Mags where it seemed to be binding and hope that fixes it. I will also take a look at the rings in the bolt because I did not assemble the bolt it came with the upper. Thanks for that link! That is a great manual on ARs. Let me give some more info on the malfunctions. It was able to expel the brass from a fired round, then the bolt would either close without picking up a round or bind up half way closed. It was sometimes odd in that you would sometimes get two to fire fine in a row than on the third round it would not pick it up and chamber it. I was able to get it to fire several magazines in a row without issue. Than someone else would try and have an issue on almost ever other round. So I am not 100 percent confident that I identified the problem. I will also clean it and apply more lube, anyone have anything they can recommend?
 
Handloads

Key word.

Almost surely your problem.

I wouldn't even bother trying to diagnose anything else until you try proper factory ammo and still have problems.

I would NOT start taking a dremel to the magazines. You are using quality magazines (at least the PMAGs), an rguns upper and HANDLOADs. The magazines aren't going to be the problem.
 
Warp, I don't think handloads are the problem they function fine in the Stag Model 3. I think it just needs to get worn in..hopefully. I will try and get a few boxes of factory ammo before I head to the range next time, just to be sure.
 
mookiie said:
Warp, I don't think handloads are the problem they function fine in the Stag Model 3. I think it just needs to get worn in..hopefully. I will try and get a few boxes of factory ammo before I head to the range next time, just to be sure.
Click to expand...

A quality gun doesn't need to be "worn in" to work.

There is no reason an AR upper needs worn in to properly function.

It certainly isn't the mags if you are using PMAGs, and they work in the other upper, and you are noticing the symptoms on all the mags.

You talked about scuffing and material loss on the mags. That indicates it's an rguns upper problem (assuming it isn't happening with the other upper and that same lower)

I will wager $ it's a combination (%/% TBD) between the rguns upper and the handloads.


But seriously, anytime you are having function issues with any gun while using handloads/reloads, the first thin you should do, before anything else, is run factory ammo to see what happens.
 
Now that I am thinking about it, I wish I had swapped out the bolt carrier groups between the two uppers to see if the malfunction followed it. I will tear it down soon and clean and lube it as well as check parts for wear/fit.
 
Status
Not open for further replies.

Similar threads

I
  • Locked
Post pics of your AR and describe your platform.
2 3
Replies
70
Views
5K
68wj
6
M
  • Locked
building my first ar- parts list
Replies
11
Views
511
HOOfan_1
H
S
  • Locked
ar-10 feed problem
Replies
20
Views
3K
madcratebuilder
M
H
  • Locked
Can you slow-cycle your AR?
Replies
15
Views
1K
briansmithwins
B
N
  • Locked
AR feeding problem, please help!!
Replies
11
Views
718
Bartholomew Roberts
B
Back
Top