Rock River AR Pistol . . . MORE PROBLEMS!

[BionicMan]

FINDINGS/SOLUTIONS IN POST #108!

Preface:

I bought this gun recently from another forum member and everything was swell until I actually took it to the range yesterday. The seller stated that he had run 30 5.56 rounds through the gun flawlessly, and that it was good to go. As it would turn out, I ran into major reliability issues. Before taking it to the range I did do a thorough detail strip and clean. (it was pretty filthy and rather dry)

Problem:
Major failure to feed and failure to eject issues. The run down of my range experience:

- loaded up a 30rd Lancer Systems magazine with Federal XM855, chambered a round, no problem
- fired 3 rounds, no problem
- fired 4th round, then FTE

The brass that didn't eject properly:



- I cleared the brass, chambered a 5th round, fired no problem
- I fired the 6th round, another FTE
- I fired the 7th round, another FTE
- I unload the mag and switch to Silver Bear .223
- I chamber a round, shoot it, again FTE
- this time I clear the brass, slingshot the charging handle, and get a FTF
- I clear the gun, insert a fresh mag of .223, hit the bolt release, and again FTF
- I repeat the last step, again FTF
- at this point I switch back to a full mag of the XM855, hit the bolt release, and now I'm getting FTF with the XM855 as well. I proceeded to try chambering a round a number of times using the bolt release and manually running the charging handle, and it wouldn't feed anything.

Disgusted with my worthless paperweight, I brought it home and took these photos of a FTF with the XM855.










. . . so what the hell is my problem here? The magazines? The gun? The Lancer System mags have rave reviews and my friend that works for them tells me they can't even keep them in stock. Considering the reputation, I wouldn't think it was the mags . . . except to me to looks like the magazine sits pretty low in the gun when it's fully seated. Any advice would be appreciated here, perhaps even the name of a gun smith in/around the Lehigh Valley that's good with AR's. Thanks!

[phoenix_iii]

Hey there.

A few considerations.

The lancer systems mags are a little different as per a review I just read on ar15.com.

I like cproduct mags, but there are many good options. I would borrow another quality mag, see if it seats the same as the ls.

Extracting and feeding can be shooter induced, have a sturdy friend give it a go as well (limp wristing or riding the recoil)

However, you should NOT have a problem loading from a locked back bolt (hence different mag). If the ammo is weak, it might now be pushing the bcg far enough back to extract and feed the rounds. Try stronger ammo, or change to a lighter spring.

[Pagoda240]

1. I would clean it and make sure it does not have steel case lacquer in the chamber.

2. Try running it a little wetter.

3. Picture of complete rifle (barrel length)

[Hawk]

Try the easiest things to fix first.

1. FTF - Try other mags. Don't load them full (one round shy).
2. FTE - Check to make sure you're not leaking gas. Make sure the gas key is tight. You can also check the alignment and tightness of the gas block.
3. FTE - Inspect and clean the chamber.
4. FTE - Check and/or replace extractor


How the Gas system works: http://www.youtube.com/watch?v=eow5t...eature=related

Gas key: http://www.youtube.com/watch?v=2tYWjQPbwS0

Gas block: http://www.youtube.com/watch?v=VEUtg_sUsA0

Extractor: http://www.youtube.com/watch?v=8l-pAw-6pUY

[bac0nfat]

First of all I would try to avoid using terms such as FTF and FTE when describing your problem, because it makes it confusing. FTF could mean "failure to fire" or "failure to feed," and FTE could me "failure to eject" or "failure to extract," all of which are completely different failures. You probably already know this but "extract" means to pull the brass out of the chamber, and "eject" means to throw the brass through the ejection port and away from the gun. A LOT of people use the terms "eject" and "extract" interchangeably, which they are not.

Anyway, I would first start by trying another magazine. In my experience, most firearm failures are magazine related. I'd try to get a hold of a magpul p-mag, they are extremely consistent and reliable.

Of course cleaning and lube are important, but there shouldn't be a need to obsessively clean an AR. As Pagoda mentioned, check for gunk in the chamber, whether you are using lacquer coated cases or not. Steel cases in general make dirty chambers because they do not expand like brass to seal the chamber off from the beginning of the barrel.

[brownman]

Do you have any other mags to try? I wonder if your Lancers are sitting too low for the next round to be picked up and chambered? I'm no AR guy, just thinking out loud, tryin to help.

Edit- this wouldnt help the extraction/ejection issues you mention though so, maybe its not the mags. IDK. Like I said INARG

[BionicMan]

I like cproduct mags, but there are many good options. I would borrow another quality mag, see if it seats the same as the ls. That's exactly what I was thinking

Extracting and feeding can be shooter induced, have a sturdy friend give it a go as well (limp wristing or riding the recoil) I tried shooting it with a sling, tucked into my shoulder, and bench rested, so I doubt that's the issue. I got it to cycle properly at least once with the sling and the tucked in method.

However, you should NOT have a problem loading from a locked back bolt (hence different mag). If the ammo is weak, it might now be pushing the bcg far enough back to extract and feed the rounds. Try stronger ammo, or change to a lighter spring. I follow your thought process, but the Federal XM855 Penetrator is a pretty stout round.

1. I would clean it and make sure it does not have steel case lacquer in the chamber. What exactly would I be looking for?

2. Try running it a little wetter. I went pretty generously with the oil right before I took it out

3. Picture of complete rifle (barrel length) 7" barrel

Hawk - excellent info, I'll check up on those things.

Baconfat - thanks for the terminology notes. The brass looked to be properly extracted, but not fully ejected.

Browman - unfortunately I don't have any other mags to try, as this is my first AR. I'll see if I can borrow some.

[magras]

was that zombie max ammo?

[wellcraft]

did the mag you used come with the gun???? AR15 mags are cheap and plentiful at most gun shops so before you condemn the gun as a paper weight pick-up a few aluminum mags and a couple of p-mags and see how the gun runs. i've read a lot of bad press in regards to c-products mags so i would personnaly stay away from them but brownells has good GI mags at reasonable prices.

did the seller give you a reason why he was selling the gun??? if different mags don't solve your problem check with rock river and see if the gun is still under warrenty. lots of gun manufacturers will honor the warrenty even if you're not the original owner.

[fastfive0]

magras...no that is not hornady zombie max....the green tip denotes it as a "military" steel penetrator round.

To the Op, as already stated, try some different mags...then let us know.