DPMS AR with feeding issues

[dj_28]

This AR is in 5.56 and when shooting .223 ammo through it, it hangs about every third shot. Would that be do to lower pressures in the .223 or does the gun have problems? I haven't fired 5.56 ammo in this gun yet (can't find any local yet).

DJ

 

[BigRugerLover]

I have a DPMS upper, have fired both 5.56 and .223, and had problems with feeding rounds (and several different mags and brands of ammo). It became reliable when I (1) lubed it up like a truck stop hot dog and (2) put 29 rounds in the 30 round mags and 19 rounds in the 20 round mags. I lubed the buffer tube and spring too. A wise old fart said that I should produce a cloud of CLP on my first shot.

Sorry I don't know about the pressures.

Now somebody is going to come along and say that's baloney, but it worked for my DPMS upper. Hope that helps.

 

[ID-shooting]

What do you consider "hang?" Failure to extract? Eject? Feed? Bolt stoppage?

Biggest culprit to an AR not completing a cycle are not offsetting the three washers in the bolt. The other is a glogged/dirty gas tube/port.

 

[dj_28]

thanks guys I'll try cleaning and lubing it up. It has only had about 40-50 rounds put through it.

DJ

 

[Waywatcher]

The bolt and carrier should be wet with lube; mags, extractor, ammo and lube are the common culprits--MEAL.

Wet enough to be spread with a finger on the contact surfaces. The DPMS owners manual actually has a good lube guide in it.

 

[BBBBill]

... Biggest culprit to an AR not completing a cycle are not offsetting the three washers in the bolt.

Not so. You have been misinformed.

 

[ID-shooting]

Not so. You have been misinformed.

Unit armorer, US Army in a previous life. You?

 

[Nicky Santoro]

OP,
The 5.56 vs. .223 is an irrelevant non-issue. The rifle should run fine on either as long as they are up to spec. Try a different mag and different ammo. Sometimes weak ammo in a new, tight gun that is under-lubricated will produce a situation which could be called "hanging". What brand of ammo are you using?

 

[j.kramer]

could be feeding problem or extractor

check buffer most dpms 5.56 dont like comercial size

oil everything up till it breaks in

 

[BBBBill]

Unit armorer, US Army in a previous life. You?

Still in. Former enlisted. E-6 when I went to OCS. I'm at 33 years now. The gas ring thing was taught forever. The Army still teaches that for some reason, but it has been disproven. The only time that it might make a difference is when the rings are already worn out and in need of replacement. If they were staggered then, it might let you run a little while longer before totally crapping out.

 

[Patrick Gookin]

What kind of ammo are you using? I used to try the Russian brands of ammo, but I would always get failures to eject and feed and all kinds of problems. I switched to brass cased ammo and I've never had a problem since. All the lube in the world wouldn't convince my AR to work properly with Russian ammo. The only Russian ammo I ever had luck with was MFS. A couple years ago it was $230 for 1000 rds and I rarely had any hickups with them.

 

[j.kramer]

What kind of ammo are you using? I used to try the Russian brands of ammo, but I would always get failures to eject and feed and all kinds of problems. I switched to brass cased ammo and I've never had a problem since. All the lube in the world wouldn't convince my AR to work properly with Russian ammo. The only Russian ammo I ever had luck with was MFS. A couple years ago it was $230 for 1000 rds and I rarely had any hickups with them.

i only use the steel ammo

add the o rings to extractor make sure good spring tension on buffer

before i do anything with new rifle i inspect all parts and clean with carb cleaner everything

then oil and break in

 

[1911 guy]

Especially a new rifle, run it pretty wet. Not sloppy, spraying lube everwhere wet, but pretty wet. I've found that after a lot of use, they require less lube, but when everything is still tight, more lube is better. I just finished building another and I run 'em practically dripping for the first 1K or so.

 

[Maj Dad]

My DPMS isn't new, but it doesn't have a lot of rounds through it, so I keep it wet (I use GI CLP). I also pull the BCG out after every 60 rds or so & put a couple drops through the holes on the side of the bolt onto the gas rings & work the bolt head several times to spread it. As long as I keep it damp it runs flawlessly.