Being an AR newbie, I'm pretty puzzled by my new AR's antics. Its jamming all the time. I might touch off a couple rounds and then a live round will get jammed with the base of the case above the bolt and the point of the round angled downward against or just past the feed ramp. The bolt will be half way closed and pressed solidly against the halfway point of the round. And the thing is JAMMED solid.

A former army at the range last night said it was probably either the mag or the buffer spring needed lube.

Any ideas? I'm going to strip it and lube everything (and hope little springs don't go flying into space when I do so).

Oh yeah, its a DPMS lower, J&T 16" upper. Mags are USA 40rd and a Who-Knows-Generic brand 20 rounder.

Duck, Get yourself some USGI mags, That sounds like your problem.

You say you are using 40 rd USA mags...and generic 20 rd mags...Well that there is you problem.  I hate to say this, but take all your USA & generic mags and throw them in the trash, they will never work correctly.

Save a few extra bucks and get some USGI used mags.  They will work, I guarantee it.  You can get either 20 or 30 rd mags. The cost will be around $20-30 each but they WILL WORK!

You will soon find, that AR15's are funny about the mags "they" use....if you use USGI you'll be all set, generic mags = JAM-O-MATIC.

Spend the $$ or you will always be upset with your AR15!

I have a new AR and use only Sanchez USGI mags. 100 rounds through it so far. Not a single problem.

When I was a Drill sgt, that happened alot, and it was always fixed with a new mag.
                     FREE

Well, maybe.  But I prefer a little science thrown in for good measure.  Yes, AR's can be fussy about mags, but most mags will  work in a properly built AR, and for 2 mags to not work is a longshot...so let's take a first step here.
First, it's not at all  unusual  for a new AR to act up a little.
Did you thoroughly clean & lube the whole gun BEFORE you went to the range? That includes taking the bolt out of the carrier and cleaning/lubing all parts.
After that is done, load one round into one of these evil mags and insert mag into gun.
Press the bolt release. (do not charge by hand)
Did the bolt/carrier go forward and chamber the round and completely lock up?
If so, fire the round.
Did the bolt/carrier lock back on the empty mag.
If successful, repeat with two rounds, then 5, then 10, etc..
Let us know what happens.
Too soon to throw away mags.  There are a lot f mags out there that are not USGI, and they fire a lot of rounds.

I have a better test.  Load the mags two rounds short of full, then strike the base of the mag on a table.  Chances are the mag lips have faired and the springs are weak.

This test is called the fountain effect, due to the mags spraying the rounds in the air.  In your rifle, the bolt will stop the mag from spraying more than a few rounds, due to the bolt stopping the flow.

A band-aid for the mags is to re-bend the lips to the correct position, then stretch the spring to give them more pressure. But due to the softness of the lips, and the weakness of the spring, the band-aid will not hold long, and once again, your back at jam-o-matic.

If nothing else, buy one USGI mag that you can function test with, and have when you need the rifle to be reliable.

Food for thought.

There are a number of things that can cause this. The USA mag can most definitely be the problem as I too have had chronic problems with one USA mag I bought. My suggestion to you is to beg, borrow, or buy a fairly new USGI mag and put it through its paces. If it continues to jam the problem is not the mag and we need to look elsewhere. Try it and get back to us.....

I really appreciate everyones input. Its unusual for a new user to post and not get blasted on the internet. You folks are great... thanks.

I went out and bought a new USGI mag. Central Industries or something like that.

My damned rifle shot fantastic. It had one failure to eject out of 200 rounds. MUCH better than before.

Of course, I finally got a sense that I am learning who this rifle is. What it wants, how it likes to be shot. We're "bonding" as it were... How else the hell are you going to shoot a rifle properly????? :)

You learn quickly, Grasshopper. Keep that rifle clean and oiled, and you'll both be happy.[:)]

Just make sure you clean it with Eds Red and lube it with break free, it will reward you like a willing mistress....  whew, talk about bonding...  Ops

DuckDawg,
We have the exact same gun (DPMS lower and J&T upper) so I thought I would share my experience with newly assembled gun. For breaking in barrel I used two 20 rd USGI mags and one 30 rd USGI mag and no jams after 200 rounds. The last 25 or so rounds were shot as fast as I could pull the trigger and still hit target.
Merry Christmas to all on AR15!
Chris
PS Hoping for 50 degree temp for X-MAS holidays
to put another 500 rounds or more through new gun, but it aint gonna happen. Drat!

The only way for me to have the scientific result is to complete the test and go back to the alleged bad mags and see if they function.

Here is a great test for any USA mag:

Unload it.
Set it on a block of wood about 2-4 feet in the air. Embankments, fences, trees, rocks, anything like that will do in a pinch.
Step back about 30-70 yards.
Take your AR15 with a fully loaded USGI mag and show that piece of shit who is the boss.
Do it 30 times.
Reload and repeat if need be.
[x]

When he mentioned the USA mags that was the first thing I keyed in on. I have 4 and they will jam every time.

Get some used USGI mags from this guy. The product is top notch. (unsolicited)
[url]http://www.arizonagunrunners.com[/url]

USA mags are junk. I threw mine away after the first so called use. USGI mags all the way!

I thought I would followup since I shot about 400 rounds this weekend and I have basically the same gun as DuckDawg. Three or four times the gun failed to feed the first round in the mag. Always the first round in the mag. I used three different USGI mags. I failed to pay attention whether or not it was the same mag each time. I guess I was to excited about getting to shoot this gun for only the second time. I shot about 200 rounds to break in barrel during the Thanksgiving.

Facts:
1. The gun was clean and lubed before I shot yesterday.
2. I was using USGI mags only.
3. The bolt locked back everytime after the last round in each mag was fired.
4. Ammo: SA 300 rd battlepacks from Kiesler's
5. No failures to fire and no failures to extract.

What should I be looking for to see if I have something other than a mag problem? Or is this normal ie, 3/4 times out of say ~ 18 mags loaded?

What puzzles me, now that I think about, I do not believe the 30 rd usgi mag was the culprit, yet this particular mag appears to be in the worst shape of the three mags by far.

Any help would be greatly appreciated.

Thanks

KY-AR15, I'm not really sure what your asking, but I will take a stab in the dark.

Start off by pulling your mags apart and cleaning them. The problem child may be just a little dirty and causing binding.  Also, since your rifle is new, it will take some time for it to polish it's self out. The one place to make sure that is lubed is the buffer.  Some people over look lubing the area during break-in.


As for cocking the rifle, I will lock the bolt back, insert a mag and rap the bottom of the mag with my palm to make sure that the mag is seated.  Then as my left hand comes up, I will tag the release button with the pad of my left hand. This releases the bolt and drives the round out the mag.  Left hand grabs the forearm, then with my right hand, I come off the pistol grip and use the palm of my right hand to give the forward assist a few raps to make sure that the bolt is locked.

Granted on the range it may be a little over kill, but you will know that the first round is loaded and ready to go.

Yeah, yeah, yeah....blah blah blah.
Please send all of your non-functioning USA mags to me and I will give them a good home for orphaned mags.
No, really...I'm serious.  PM me (if you care to put your mags where your mouth is) and I will give you my address and I will pay the shipping.

Sorry, but I have used every mag known to man in my AR's an I have not found one yet that did not perform perfectly, discounting bent lips/bad springs, cracked seams. Not all would drop free, especially those nasty Orlites & Thermolds, but they all fired first round through to the last.

My offer stands and I will give an honest range report on every one.  ALl who know me know that my word is good.  I will send $10 to the owner for every mag that fails to cycle properly.
I expect I will corner the market on USA mags.

Royce,
I'm sorry to hear that the someone has pissed in your Wheaties. But, unless someone left pecker tracks that lead back here, You may just want to get a new bowl and start over.

The only advice that I can give you is to try to play nice, and don't try to change the beliefs of the masses overnight.
I should know cause I have tried the same, and often find myself having to bang my head off the key board every time I read a post that is so blatantly wrong.

If nothing else, take deep breaths, count to ten, and repeat after me," I will not poke the Newbies with sharp sticks", even if they need it.

Dano

Dano,
Thanks for your input and advice. It is always mucho appreciated to receive input from experienced AR15er's based on their experiences and knowledge for those of us that are new to shooting and learning the operation of the AR15.
My question/problem was specified in the second sentence of my previous post ie, failure to feed the first round in the mag. This happened 3 or 4 times out of approximately 15 or so mags loaded. To me this would be unacceptable in combat. For plinking in the nearest creek or at the range who cares other than the frustration.

I think I will order some new mag springs (not sure where to get them) and lube the buffer/spring and go from there.

Is CLP ok for the buffer and action spring or should I use some type of grease?

Thanks again to everybody for their responses!
Chris

KY-AR15
Only use CLP in the rifle.  It is a cleaner, lube, and a cleaner.  If you mix CLP with anything else, the two will gum up due to the cleaner in CLP. The two items that you should be using on your rifle is CLP for lube/cleaner, and a good cooper solvent to clean the barrel.  CLP will not dissolve the cooper fouling in the barrel, so here is where the solvent is used.
As for the buffer, you may as well pull it, and give the buffer and spring a shot of CLP.

Note: There are some other lubes on the market that could also be used, it just that I haven't had a chance to try them out, and can only suggest CLP.


Bottom line is that your rifle is still new and all the bearing surfaces are still rough from the anodizing.  By keeping the bearing surfaces(upper and bolt/carrier) a little wet with CLP, it allows the parts to mate faster, and the extra lube will carry away some of the anodizing/fouling. Once the rifle has broken in, then back off on the CLP.

Regarding combat and the rifle. Normally, the rifles are carried around for weeks, and cleaned at least 4 times a day.  By the time the rifles gets shot, They have been polished/mated by just the cleaning.  

If you would like to do this yourself at home, then every day, hand your rifle to your wife after cleaning and have her throw it back at you, claming it still dirty.  
After the third/fourth time re-cleaning and having the rifle thrown back at you, then you can put it back in lock-up.
Do this for at least 6 weeks, and see if you still have binding problems.
Also, you have to find a sand/mud pudles to roll around in (holding the rifle), before you clean the weapon each day.  That way, you have something to clean out of the rifle, since you only get to fire it on the last two weeks of the ordeal.
I can go on, but I think that you get the point.

Okay, I deserved that.  I'll bet you just took that whole speech from something I posted about YOU about a year ago and changed the name to Royce!  I'll behave.

KY, I am bothered by the fact that this only happens on your first round.  Normally, I would have gone after the mag, but the right-side or left-side feed problem happens anytime you stop firing, not just the first round.
I also would have looked at the feed ramp, but again, you should not be going through the mag without a repeat of the problem.

Question:  How are you charging the gun for the first round?  Are you rapping the bottom of the mag to get a positive seat?  Are you letting the bolt go forward by hand or releasing the bolt/stop on a locked-back bolt/carrier?

PS:  Dano, not one person took me up on the USA mag offer.  Why is everyone holding onto bad mags?

Maybe it's a case of not many people have them to begin with. I had a couple of USA mags once and used them as targets. I was tired of wasting paper plates.

FWIW, the USA mags for 7.62x39 AR's are about the best available. But for standard AR's, they are simply JUNK. Go ahead and scientifically de-bug them, and they will still be JUNK. You can't polish a turd.

KY, I am bothered by the fact that this only happens on your first round. Normally, I would have gone after the mag, but the right-side or left-side feed problem happens anytime you stop firing, not just the first round.
I also would have looked at the feed ramp, but again, you should not be going through the mag without a repeat of the problem.

Question:
How are you charging the gun for the first round?
Are you rapping the bottom of the mag to get a positive seat?
Are you letting the bolt go forward by hand or releasing the bolt/stop on a locked-back bolt/carrier?

I need to talk to my son to get answers to your questions. The gun was jamming on him (his AR15). I was busy shooting a Bushy, an AK 47, and several WWI and WWII vintage pistols that a friend has.

My son is a college student (minor in Military Science - ROTC scholarship)and contracted with the Army. He has been taught how to take apart and clean M16, has shot FA and 3 shot burst models on many occassions. I'm fairly confident the instructors at this college are competent based on their military bio's ie one is ex-Delta.
He will be back in town tomorrow and I will followup with answers to your questions.

I need to investigate (actually pay more attention) the next time out to see exactly which mags and under what scenarios it is happening.

I tried my best mag today several times with one round in the mag, releasing bolt catch on locked-back bolt/carrier and it never jammed.

I dunno! [>:/]

Thanks to everybody for their suggestions and help.

KY, over on this main page are the moderator names. Click on Tweak and drop him an email or IM. He is really good at troubleshooting over the net.

If it were my AR I would ditch the USA mags and try USGI's, which you did.

Insert an empty mag into the magwell and see if it seems "loose". It may be that you need to turn the mag catch latch in one more turn if you can.

Have someone hold the rifle while they chamber a round and watch it go in.
Have them "ride" the charging handle in to see if it looks like the bolt is picking up the round or if it is just flipping it up.
From what you described your "cure" may be the green followers in your mag.

The next thing it could be is that your feed ramps are dirty of have some crap on them. Feel them for anything that may cause a misfeed.

Split the upper form the lower and look at the bottom of the bolt and the top of the hammer. Does it look like you are getting exsessive wear?

The last thing that I can think of is for you to clean your rifle dry and cycle the bolt a few hundred times to work the metal parts together. Clean it up and lube the shit out of it with CLP, I mean lube it till it is bleeding CLP, then go fire it and see what happens.

Good luck!

Dano, Royce, and USN_Joe,
Thanks for the suggestions and I will try all of them to see if I can narrow down the problem.

I failed to mention that I adjusted the mag catch one turn and lubed the buffer/spring prior to testing one round in my best used usgi mag which resulted in no jams. I chambered a round using both methods ie charging handle and releasing bolt catch on locked-back bolt/carrier.

I doubt my son was overloading the mag as he mentioned to me several weeks before we shot that he was taught to load 2-shy of mag capacity. It's possible he lost count though.

Chris

Overloading of mags is another bullshit AR15 fairytail. The problem was with the black followers in the USGI mags, the would tilt down too far to allow the next round to be stripped off the top of the mag. The green followers that are now used were the cure for that "problem". I always load my mags to the max, that's what they were meant to hold, right!

Thanks USN_Joe. Where is the best place online to buy green followers and new springs? I doubt my local gun shops carry these items but they might.

KY, you need to slow down a bit. If you are going to find out the REAL problems, then you can't keep fixing things while tracking a problem...otherwise you will never know what really happened.
Finish one cause & effect path before you replace anything else.  You need contants to solve problems.
And I still want to see the USA mags tested after all else is working properly.

Royce,
I agree for the most part. [;)]
I'm not sure what you mean by your last sentence as I am using USGI mags only.
Later,
Chris

USNJoe_Retired,  

Tweak has been MIA for a while, and the rest of use have been helping out, trying to fill his shoes.

KY-AR15,
When you get a chance to watch your son use the weapon, is he closing the bolt, then installing the mag and going for the cocking handle?  If so, then chances are he is is not getting the mag fully seated, due to the added force of the bolt pressing down on the top mag. He may be riding the cocking handle too. Depending on his training, and what type of rifle used, he may be treating the rifle a little too gently if he is used to a bolt action rifle.

I have 8 USA mags and they all function fine.

but this has to be bad magazines (the back of the case should never end up ontop of the bolt)< this can cause your gas tube to become bent (deadlining your rifle) Try new mags.

Dano,
Good suggestions. I will get him to show me today. He has been using M16/M4 in ROTC marksmanship class. From observing him handling the gun, he is not gentle, for sure.
Bolt action .243 or .270 when we deer hunt.

Chris