DPMS jamming and not feeding

[Marc]

when i go out to shoot my DPMS it does nothing but jam and if it doesnt jam it wont feed. i swapped from a regular buffer to a H2 buffer and changed my bolt over to an M16 bolt and it still has these problems. most of the time the rifle doesnt extract the round and tries to feed another one in while the spent brass is still in the breach, and when it doesnt feed well thats pretty much says it right there. the bolt wont catch the next round and bring it into the camber. a friend of mine said it could most likely be the gas system in it, sayin i dont have enough pressure which is why my rifle isnt cycling everytime correctly.


any help is very appriciated

Marc

 

[melensdad]

Is the gun new? Has this happened before?

For the most part you don't need to clean the gas tubes, many recommend you never put anything into the tubes to try to wipe them out. But there are occasional clogs in tubes, I will run gun cleaning solvent in my tubes from time to time you may want to try that see if you get a free flow of solvent, if so then there is no clog.

Also is the gun well oiled? ARs seem to like to be liberally lubed.

 

[Paul]

the m16 and ar15 bolt are the same. the carrier is the thing that is different.

did you try different mags? or the same one?

i run my ar dry and it has never missed a step

 

[Marc]

the carrier is what i swapped out, and the gun is bought new and is extremely well lubed. this has been happening to me for the longest time. after i shoot it i clean it very well. and as for mags it happens to me irregardless of what mag i am using. and would eezox lube work for cleaning the gas tube?

 

[melensdad]

and would eezox lube work for cleaning the gas tube?

I don't know that brand, but any of the gun degreasers/solvents that come in a spray can with a directional nozzle tube will do the trick. If you spray into the tube and it drains out the barrel then you either flushed out the obstruction or you never had one, meaning the problem is in another place.

FWIW, I've never had good luck with DPMS. Others claim them to be good as gold.

 

[Donnelly]

It sounds like something might be causing drag on your bolt carrier group. You are not by chance resting the gun on the magazine while shooting it, are you? This could possibly cause enough drag to cause a malfunction.

 

[Marc]

no cause when i shoot it im standing. ans shooting free hand

 

[smokingman]

It is an AR rifle...you can not expect it to actually function can you?
...ok that may be a bit extreme. Any chance you are using poor ammo? I am not an AR expert but I would inspect spent cases and look for drag marks,check the gas tube with a light,dry lube it with some graphite and get rid of excess oil.Try at least one other type of ammo. If none of that works the only sure solution is to trade it for an AK

 

[KDUBCR250]

Does it lock back after the last round (short-stroking ) ? You might need to adjust your mag catch and or put a o-ring in the extractor . Be nice if you could take a pic of the jam and maybe even the bottom of the bolt carrier .

 

[Marc]

Does it lock back after the last round (short-stroking ) ?

nope it doesnt lock back. i just jams or doesnt feed and the chamber is closed and there is no round in the chamber but there are rounds in the mag.

 

[KDUBCR250]

Did you check and make sure your gas key is tight and properly staked and make sure its lined up with the gas tube ? Have you inspected the gas rings and the inside of the bolt carrier where it goes ?

 

[TheGhostRider]

Your rifle is short stroking. A symptom of low pressure.
Start by: Putting the regular weight buffer back in.
Confirm that the gas key is tight.

What kind of ammo are you shooting?

With a new rifle it is particularly important to use full pressure ammo such as M193 ball or other 5.56 ammo.

.223 ammo may not have enough pressure to run your rifle until you've broken it in, so it would be best at this time to run a regular buffer as a H2 buffer will make the problem of low pressure worse. The idea of using the H2 buffer is to slow down the bolt inertia because the carbine length gas systems tend to over pressure due to the timing curves.

If running full pressure ammo takes care of the short stroking then you can try the H2 buffer. At that point you should notice an improvement in recoil impulse and recovery times.

PS: Something I forgot to ad...
If these steps don't take care of your problem there is something else that you should check.
Chamber dimensions. DPMS is known to have undersized chamber dimensions. Even though their marketed as having NATO spec chambers a large percentage do not. They have .223 chambers. This can cause all kinds of mischief when trying to troubleshoot feeding problems.
You should probably seek out a qualified AR smith to verify your chamber size and if necessary use a Ned Christiansen chamber reamer. This will bring your chamber up to spec and eliminate any doubt about what ammo you can shoot and most likely this will end your feed issues.

 

[ATM]

^Second post on INGO. This is not your first rodeo is it?

 

[9rows]

^post #2. This is not your first rodeo is it?

+1

that is a hard core post

 

[Marc]

What kind of ammo are you shooting?

i am shooting .223 55gr remington white box. i had the gun cleaned today and chunks of carbon literally fell into the barrel when they guy sprayed the cleaner in the gas tube, and thats something i dont get, my dpms has less than 1k rounds through it.

 

[Marc]

oh and the gas key is on and sealed, thats another thing the guy looked at.

 

[Marc]

well i went out and tested it and it doesnt jam anymore now it just doesnt feed. which i think might be due to a soft spring in the mag. the mags i am using were brought home from iraq and were used in long and many fights in faluja and also assualts that were made by al queda on the abu grab prison (my brother brought them home for me as a souvenier... yea those mags have seen some ****) i got 2 new mags that came with my dpms and im gonna try those next. but i switched my ammo from remington 55gr to wolf 62gr non corrosive and my ar functiond alot better. i still think i might need a heavier buffer also so i can slow my bolt down alittle more, i think my gas system is fine but i might want to get my port opened up alittle more.

 

[USPc40]

Since your gas key is ok and gas tube is now cleaned out, try this:
Ref. post #12
(Assuming you are still using the H2 buffer)
Buy a box of M193 5.56 ammo.
1- Load 1 round in a "good" magazine.
2- Insert mag., chamber the round, and fire.
Did the bolt lock back ? If not, put the standard buffer back in and repeat. If it did lock back, load 2 rounds in magazine and repeat 2. If the 2nd. round feeds and bolt locks back after firing 2 rounds, sounds like the ammo.

 

[cosermann]

Is this carbine (16") or a rifle (20") sized gun?
What happens if you chamber a single round and fire it with an empty magazine in?

 

[TheGhostRider]

What's the status with your rifle? Hope all is well now!