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Mac5.56
08-13-09, 00:09
Someone the other day was trying to use his brothers AR as an example in an argument regarding why the AK is better then the AR. Gun in question is a 20 inch barrel. He stated that his brothers AR has had 4-5 stove pipe malfunctions, and thus this certifies that the AK is a better gun.

So without getting into the AK vs AR debate, what are some of the mechanical malfunctions that would cause a stove pipe in an AR? I am thinking over gassing, and a week extractor? Am I right on this?
bkb0000
08-13-09, 00:38
most likely the ejector, rather than extractor
Iraqgunz
08-13-09, 00:43
Roger that! And I would much rather replace an ejector in an AR than an AK. AK ejectors are built into the receiver. Wonder which one is easier to fix? Hmmm....


most likely the ejector, rather than extractor
Quib
08-13-09, 05:52
I’m betting quite a few folks neglect the ejector during lubrication and PM.

The -10 Operators Manual has you place a drop of CLP on the ejector. Next a spent case is used to work the ejector back and forth, to allow the lube to work it’s way into the ejector pocket and down into the ejector spring.

Newer weapons during cycling, will often times shed tiny flakes of brass from the cases as they are ejecting. These flakes of brass can make their way into the ejector pocket along with the normal carbon during firing, hindering proper ejection.
larry0071
08-13-09, 08:24
Based on the new understanding that I am starting to get of the buffer weights and buffer spring as well as bolt carrier weight (AF vs. SA), could the stove pipe issue have anything to do with too light a buffer or spring, or too large a hole (erosion) into the gas system from the barrel? Any of those would potentially make his action go faster than planned, and maybe cause this....no?

Just asking, not telling.
bkb0000
08-13-09, 10:30
Based on the new understanding that I am starting to get of the buffer weights and buffer spring as well as bolt carrier weight (AF vs. SA), could the stove pipe issue have anything to do with too light a buffer or spring, or too large a hole (erosion) into the gas system from the barrel? Any of those would potentially make his action go faster than planned, and maybe cause this....no?

Just asking, not telling.

not really.. if the ejector is working right, it'll eject brasso no matter how fast or slow the action cycles.

the AR bolt keeps constant ejecting spring tension- the moment the mouth of the cartridge clears the receiver, that sucker's gone. the AR can eject brass even while short stroking.
BushmasterFanBoy
08-13-09, 11:23
not really.. if the ejector is working right, it'll eject brasso no matter how fast or slow the action cycles.

the AR bolt keeps constant ejecting spring tension- the moment the mouth of the cartridge clears the receiver, that sucker's gone. the AR can eject brass even while short stroking.

That's assuming the extractor can keep a grip on the case long enough for that to occur. It's not uncommon for overgassed/weak buffer spring/light buffer/weak extractor spring guns to drop the case before the ejector has a chance to push it out. This may result in a stovepipe, but more commonly just wedges the empty in the charging handle channel. Goody. :eek:
Thomas M-4
08-13-09, 12:04
what is the proper way to check ejector tension?
eodinert
08-14-09, 02:27
If a gun is over gassed, or the chamber is not to spec, these can manifest themselves as an 'ejection' problem.

Added weight of a heavy buffer can delay movement of the bolt carrier assembly, which will help mask a problem with too much gas, and appear to be a 'failure to eject' problem, although this is most common on carbines and short barrel guns.

The difficulty in diagnosing a problem is that everything is interconnected, and issues have to be eliminated or isolated to determine what's actually causing the problem. Even something like a loose bolt carrier key can cause problems that at first glance look ejection related (and that's even before we get started on ammo).

My first question, for a 20 inch gun, would be 'who made it?'. Some makers are known to have tight or out of spec chambers.

So for a hypothetical, there is really no way to say. The weapon has to work as a system, and when it's built right, it does.