Jim, thats my club too! Which Jim is this?
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AR malfunctioning, need advice
- Thread starter StoneBear
- Start date
Jim, thats my club too! Which Jim is this?
Got to the range this weekend, but wasn't able to diagnose the problem as I would have liked. Obviously, with my full intention of finding what causes this firearm to malfunction, it runs better than it ever has. However, it is still not operating to an acceptable level.
I had planned to run these tests:
As seen from the attached photos, I swapped the standard handguard back on in place of the Daniel Defense quad rail. That was the only real change. As always, the gun was clean and well lubed. I did push the gas tube back towards the block while the rifle was apart for examination, but I dont think this would fix a gas leak problem if there was one up there.
I fired 110 rounds through the Olympic. 90 rounds were Fiocchi 55gr. FMJ and the remaining 20 were PMC 55gr FMJ. I noticed no difference in performance. I used 5 different magazines 4 pre-ban 30 rounders and a ten round Stag mag. A magazine in use during a failure to lock open was taken out of the rotation.
The first seven shots were singles to test if the bolt carrier would lock open, 6 out of 7 times it did. Of all the mags emptied through the rest of the testing (approximately 20, with varying numbers of rounds in each) I believe I had only one additional failure to lock open.
Of the 110 rounds I had 5 stove pipe jams and 9 failures to eject. The failures to eject were all on the last round of the magazine and the shell was found sitting loose in the chamber. Simply rolling the rifle to the right was enough to dump the empty shell. I believe I had at least one of these with every mag used.
The overall pattern of ejected shells on the ground ranged from 0' (right at my feet) to approximately 5', all kicking out at a 2 o'clock trajectory. Most brass landed about 3ft from me.
The first jam didn't come until the 51st round was fired. I was very surprised at how well the rifle was running. We have had the rifle out plenty of times and you could count on at least 6-7 jams by this point. The 2nd jam came on the 76th round, 3rd jam came on the 103rd round, 4th on 104th and 5th on 108th. Ran out of ammo. [sad2] which is never good. However, it is clear to see that jams were starting to come with increased regularity.
Take away message:
Though 4.5% stove pipes isn't horrible, I wouldn't like to see this many with mid-grade and up quality ammo. The additional 8.2% failures to eject are not the end of the world either as they are coming on the last round of the mag and are easily handled. However, this is still not acceptable for the following reason: I am guessing these two different failures are actually one and the same. The stove pipe jam is simply happening while I still have rounds in the mag that are attempting to feed into the chamber. Therefore, I also suspect that any of the 9 failures to eject would also result in the more problematic "stove pipe" if they had any rounds coming up behind them.The total mechanical failure during this outing was, 12.7%. Not including the failures of the bolt to lock open.
Though the bolt didn't lock open a couple times, I am looking to the mags as the culprit for that problem. For the failures to eject, I am thinking possible extractor wear, again I did replace the ejector and extractor springs, but not the actual ejector or extractor.
What do you guys think?
Sorry I don't have more interesting info to report right now, I will hopefully do this again next weekend and see if the rifle really starts acting up again.
I had planned to run these tests:
But the firearm was not malfunctioning enough to start swapping parts. I dont think I would have learned anything .
As seen from the attached photos, I swapped the standard handguard back on in place of the Daniel Defense quad rail. That was the only real change. As always, the gun was clean and well lubed. I did push the gas tube back towards the block while the rifle was apart for examination, but I dont think this would fix a gas leak problem if there was one up there.
I fired 110 rounds through the Olympic. 90 rounds were Fiocchi 55gr. FMJ and the remaining 20 were PMC 55gr FMJ. I noticed no difference in performance. I used 5 different magazines 4 pre-ban 30 rounders and a ten round Stag mag. A magazine in use during a failure to lock open was taken out of the rotation.
The first seven shots were singles to test if the bolt carrier would lock open, 6 out of 7 times it did. Of all the mags emptied through the rest of the testing (approximately 20, with varying numbers of rounds in each) I believe I had only one additional failure to lock open.
Of the 110 rounds I had 5 stove pipe jams and 9 failures to eject. The failures to eject were all on the last round of the magazine and the shell was found sitting loose in the chamber. Simply rolling the rifle to the right was enough to dump the empty shell. I believe I had at least one of these with every mag used.
The overall pattern of ejected shells on the ground ranged from 0' (right at my feet) to approximately 5', all kicking out at a 2 o'clock trajectory. Most brass landed about 3ft from me.
The first jam didn't come until the 51st round was fired. I was very surprised at how well the rifle was running. We have had the rifle out plenty of times and you could count on at least 6-7 jams by this point. The 2nd jam came on the 76th round, 3rd jam came on the 103rd round, 4th on 104th and 5th on 108th. Ran out of ammo. [sad2] which is never good. However, it is clear to see that jams were starting to come with increased regularity.
Take away message:
Though 4.5% stove pipes isn't horrible, I wouldn't like to see this many with mid-grade and up quality ammo. The additional 8.2% failures to eject are not the end of the world either as they are coming on the last round of the mag and are easily handled. However, this is still not acceptable for the following reason: I am guessing these two different failures are actually one and the same. The stove pipe jam is simply happening while I still have rounds in the mag that are attempting to feed into the chamber. Therefore, I also suspect that any of the 9 failures to eject would also result in the more problematic "stove pipe" if they had any rounds coming up behind them.The total mechanical failure during this outing was, 12.7%. Not including the failures of the bolt to lock open.
Though the bolt didn't lock open a couple times, I am looking to the mags as the culprit for that problem. For the failures to eject, I am thinking possible extractor wear, again I did replace the ejector and extractor springs, but not the actual ejector or extractor.
What do you guys think?
Sorry I don't have more interesting info to report right now, I will hopefully do this again next weekend and see if the rifle really starts acting up again.
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Crappy mags, worn mag springs will cause the bolt to fail to lock back. Crappy bolt catch, like the one I installed from Colt on my RRA lower, caused this failure as well. Looks like your brass is ejecting and hitting the brass deflector properly though? Mapul PMAGS can be found at a fair price.
Sheckie
Sheckie
I did replace the little extractor spring buffer/ insert. Yes, it was black. The spring for the ejector was replaced as well. Im not certain if the tension is good or not, it feels solid. The tension should be great as I bought both the extractor spring and ejector spring as a package upgrade. They are supposed to work together and increase the power by which the spent shells are removed from the rifle.
A bit off the topic, but what are some of the standard mechanical upgrades people tend to do to their ARs to increase reliability? Im not really talking about furniture, barrels or triggers, but the basic operating mechanisms, like increase extractor and ejector spring tensions.
Although you did take a very mathematical approach to in regards to malfunctions, did you ever clean up the gas block area to see if you are indeed leaking gas? I would say without a doubt that you have some gas leakage from the white and black residue surrounding the gas block. If the gas block is leaking then it can be linked to all the problems that you are having including the bolt not locking back on the last round. Not only can that be caused by a bad magazine but short stroking would lead to that as well.
Mike, I agree, I definitely think there is some gas leaking going on.
As obvious as it is, I overlooked cleaning the barrel under the gas tube to check additional leakage, I will do that this weekend.
Ill check into the buffer spring tonight.
As obvious as it is, I overlooked cleaning the barrel under the gas tube to check additional leakage, I will do that this weekend.
Ill check into the buffer spring tonight.
Remsport Mfg
NES Member
Bring it by and we will have it fixed short time. Your shot gun approch is only costing you money. It will cost you less just to take the ride then to keep putting in money and getting no positive results.
Thanks
John
Thanks
John
