Ruger AR-556 problems

M

mukjp22m

New member
I bought a new AR-556 because of the raving reviews. I saw many reviews where they pulled the rifle from the box, loaded it, and successfully ran hundreds of rounds through it.

Not me. I cleaned mine thoroughly first. Mind you, I've owned MANY semi-auto rifles (but never an AR-15) and haven't had issues. First 20-30 rounds ran fine, though I noticed the last shot hold open was not working. This was on the pmag that came with it, as well as another brand. In both cases, if I manually pull the handle back, the empty magazine will correctly cause it to hold open.

After 30 rounds or so, it began failing to feed. Ejection never failed, but it was denting the side of the round and jamming up bad when trying to load the next round. That was happening every 3-5 rounds, and soon it began missing the subsequent round entirely and almost every time. It would just eject and then load nothing at all.

A guy who worked at the range looked at it and thought maybe I put too much lube on the bolt (not the BCG, just the bolt itself). He cleaned it up and then it worked fine for the final ~30 rounds I shot. I don't really put a lot of oil on my guns and this has never been an issue. Are AR's that hard to keep happy? I doubt it. Plus, all those reviews where people didn't even clean the factory grease off of it.

Any experiences like this?
 
Short stroke

After hours of research, the problem is obviously short stroking. It never locks back on empty, and it sometimes doesn't pick up the round or tries to pick it up halfway down the cartridge, causing a jam.

So why? Gas key is not loose and slides easily over gas tube. Is it possible Ruger installed too heavy a recoil spring?
 
I doubt that Ruger installed to heavy of a recoil spring. Call Ruger and speak with a customer service representative, they may have you send the rifle for repair. Don't let that bother you, what you'll get back is a rifle which has been corrected and personally inspected.
 
Yeah its definitely short stroking...

Might be an issue with the piston, or the adjustable gas... or the gas block itself.


Double check the piston system, pay close attention to the manual, look up some videos online, and confirm parts are like they should be. Then try shooting it again...

If that does not help, call up Ruger for a return, and they will make sure they get it working right.
 
I guess that myth about pistons being better than DI is debunked. Yes DI can short stroke, but ive never seen one do it right out of the box. Ruger has been known to have spotty issues with QC in some of their handguns (SR9 C). Too much oil? Na. Youd have to soak it in a barrel of oil to get that problem with that regularity. Idk much about piston ARs but it sure sounds like something wasnt up to snuff when it left the factory.
 
Stay calm and Goosefraba : ) I've had a few new AR's do this including one that I built and in my experience it's usually a question of figuring out why your not getting a good lock-up with the bolt and/or why there is a loss of pressure in the cycle. I usually start with the spent cases to look for clues. It can take time for a gunsmith to figure these out with the weapon in hand--so don't expect quick resolution over the net necessarily. : )
 
Ah... I keep forgetting they released a DI version. If it isn't the piston, then yeah...

The gas block can be misaligned, or somehow the gas tube is blocked. I would doubt it's the buffer, but going to a lighter one may hide the problem and get it working, but an AR should work pretty well with 223 ammo and a H2 buffer.
 
Strange as this may sound but a poorly pinned gas block could cause this.
I have seen of a couple rifles where the roll pin for the gas block was slightly under sized. The block stayed tight at first but after a few rounds started shifting and chocking off just enough gas to cause problem just like the OP's
It does not take much to cause a cycling issue when the gas psi is off.
Good luck, I hate chasing gas issues.:)
 
This is conjecture

It could also be hyper-function. The bolt group is moving too fast for the magazine. As the bolt travels rearward, it pushes the cartridge down slightly which in turn pushes the follower down, compressing the magazine spring. When the bolt clears the magazine, the spring pushes the follower up and with it, the cartridge.

If the bolt is moving too fast, then the spring pushing the follower isn't fast enough so the bolt crashes into the mid-section of the cartridge instead of stripping it off from the rear of the magazine.

Without having to examine it myself or to shoot it with various ammunition and magazines, it's hard to say.
 
Try a different magazine(or 2). Even P-mags can be defective. Loading up a full 30 round mag and blasting away is NEVER the appropriate way to begin with an AR.
Using a magazine known to be functional, do the bolt travel test. Load ONE round in the mag, chamber it, and fire. The bolt should lock back. Do this 5 times. If the bolt locks back every time, bolt travel(gas flow) is adequate.
With that knowledge, you can begin to determine your next step in resolving the problem(if it still exists).
 
I have the gen 2 PMAG that came with it, and also a stainless steel 30 round blackhawk mag. Both behaved the same.

I did not load a mag and blast through it. In fact, I was testing all different kinds of ammo for accuracy and was only loading about 3 rounds at a time. The bolt never locked open on either magazine at any time, probably with 15-20 opportunities to do so. However, if I pull the charging handle manually on an empty mag, it does hold.

As I think about it, it seems that the jamming or empty chamber issues started to occur once I began loading more rounds into the (brand new) magazines. So, the rounds were being pushed up with more force. However, after the guy at the range cleaned the bolt, then it was working fine in either scenario, except that it continued to never hold open on last shot.

Tomorrow I'm taking it back to the range. If it has the problem again, I'm going to swap out the BCG with a friend's BCG that is known to work. That should help diagnose. Also, i'm going to call Ruger now to see if they know of any issues.

One more thing, I noticed that it is difficult to get the bolt back into the carrier when re-inserting it after cleaning. I have to slap it to get it in. Once in and reassembled, it moves without much effort, but not freely enough where gravity or a flick of the wrist can pull the bolt into the out position. Is this normal?
 
Talked to Ruger. The rep seemed quite certain that having 2 of 3 gas rings lined up would cause the issue. I dismissed it when I saw the 3rd ring staggered when I disassembled the gun afterwards, assuming that the 3rd ring would then catch the gas.

How can that be the cause? Those rings move freely. I would think that would be a severe and rampant problem in the military if AR's were that touchy. Those rings surely would line up on occasion just out of pure statistics.
 
Once again, in that article it says that the alignment of the rings is not important. 99% of sources say that. I'll give it one more try tomorrow, then it's going back to Ruger if it fails again.
 
Do the tests listed, for the rings. That will verify if they are tight enough in the cylinder. You can have a leak around the firing pin stem, if its out of tolerance, and from under the base of the bolt key, if it isn't seating itself. There could also be too loose of a fit in the cylinder of the bolt key, that the gas tube sticks into.

These very problems are why they're looking at a piston rod actuated bolt.

AR-15_Checkout by Will Matney, on Flickr
 
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If the bolt has never locked back on an empty mag, there's a problem somewhere. Is the bolt catch stuck or does it work fairly easily when moved manually? It always works when manually cycling the bolt with an empty mag in place?
There may be a "gas leak" but I'd lean toward an improperly drilled or sized gas port or misaligned gas block. I just don't see bolt problems unless it's a manufacturing defect. You should be able to feel the gas rings compress into the bore of the bolt carrier as the bolt is pushed into place. Those gaps in the gas rings are mostly closed when the bolt squeezes into the bolt carrier. There again, gas ring gap is less an issue than many make it to be and causes symptoms different than what has been related.
Sorry if I stepped on toes but that's quite often the comments I see. "I loaded a mag and blasted it at random to test my AR and ???? happened".
 
After 30 rounds or so, it began failing to feed. Ejection never failed, but it was denting the side of the round and jamming up bad when trying to load the next round. That was happening every 3-5 rounds, and soon it began missing the subsequent round entirely and almost every time. It would just eject and then load nothing at all.
Click to expand...

Too me this just sounds like a erratic timing issue.
Gas block leaking, bolt key leaking, gas tube that was not seated well in the block and after a few rounds has been damaged and now leaking.

The the guy at the range pulled the BCG out and cleaned everything and for a few rounds it worked as designed.
Something is constantly changing in the gas system.

The OP has swapped mags and amount of ammo loaded in the mags and that had no effect.

Like I said, I hate gas system problem.
 
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