A1 Upper troubles.

bigtattoo79 · Dec 8, 2013

I shoot one shot the gun cycles but doesn't pick up a round so I pull the charging handle back let it go and it then picks up the round. It does this every shot. I've tried 4) types of ammo and 4) mags that all work fine in my A2 so I'm sure it's not the ammo or mags.
Any ideas what I should check 1st?

scooterj · Dec 8, 2013

Gas tube could be partially blocked or gas block port may not be lined up with hole in barrel.

bigtattoo79 · Dec 8, 2013

scooterj said:
Gas tube could be partially blocked or gas block port may not be lined up with hole in barrel.

Thanks I will check it when I get home.

Jack · Dec 8, 2013

Just for my own curiosity, where'd you get the upper, what components are in it, and who put it together?

rockmup · Dec 8, 2013

Jack said:
Just for my own curiosity, where'd you get the upper, what components are in it, and who put it together?

Why, you don't know ?

bigtattoo79 · Dec 8, 2013

Jack said:
Just for my own curiosity, where'd you get the upper, what components are in it, and who put it together?

It's an Olympic Arms upper. I bought it used.

bigtattoo79 · Dec 8, 2013

OK is blowing air though the tube enough to tell if its clear??

Jack · Dec 8, 2013

rockmup said:
Why, you don't know ?

How/why would I know?

rockmup · Dec 8, 2013

bigtattoo79 said:
OK is blowing air though the tube enough to tell if its clear??

No, not really but I shot it after I cut the barrel down and it worked fine.

Are you just blowing into the barrel or using compressed air ? Plugging the chamber ?

Jack said:
How/why would I know?

It was an attempt at levity.

bigtattoo79 · Dec 8, 2013

rockmup said:
No, not really but I shot it after I cut the barrel down and it worked fine.

Are you just blowing into the barrel or using compressed air ? Plugging the chamber ?

Compressed Air and Yes.

Jack · Dec 8, 2013

rockmup said:
No, not really but I shot it after I cut the barrel down and it worked fine.

Are you just blowing into the barrel or using compressed air ? Plugging the chamber ?

It was an attempt at levity.

Ah, makes more sense now.

bigtattoo79 · Dec 8, 2013

Anyone know any tricks to see if the gas block is open ? Only thing I can see to do is pull the front sight block?

gunslinger06 · Dec 8, 2013

Are you able to try it on another lower? That would eliminate any issues with the buffer, spring, or tube. I would try that first.

Is the front sight pinned on? If so, its probably not clogged. If its a bolt-on the hole in the sight may not be lined up with the hole in the barrel.

Is the barrel factory?

Sent from my SAMSUNG-SGH-I997 using Tapatalk 2

rockmup · Dec 8, 2013

bigtattoo79 said:
Anyone know any tricks to see if the gas block is open ? Only thing I can see to do is pull the front sight block?

If your plugging the chamber and putting air through the muzzle and you're getting air through the gas tube then thats probably not your issue. That gas block is pinned, not a set screw, it's not going to move on you.

Are you using the buffer and spring I sent in the other box ? Or did it not show up yet ?

bigtattoo79 · Dec 8, 2013

rockmup said:
If your plugging the chamber and putting air through the muzzle and you're getting air through the gas tube then thats probably not your issue. That gas block is pinned, not a set screw, it's not going to move on you.

Are you using the buffer and spring I sent in the other box ? Or did it not show up yet ?

Man it feels like a ton of air is going though the tube to me.

Yes it is the buffer and spring you sent.

bigtattoo79 · Dec 8, 2013

gunslinger06 said:
Are you able to try it on another lower? That would eliminate any issues with the buffer, spring, or tube. I would try that first.

Is the front sight pinned on? If so, its probably not clogged. If its a bolt-on the hole in the sight may not be lined up with the hole in the barrel.

Is the barrel factory?

Sent from my SAMSUNG-SGH-I997 using Tapatalk 2

I do have another lower I can try it on didn't even think about that.

Front sight is pinned.

It is a factory barrel but has been cut shorter.

gunslinger06 · Dec 8, 2013

Depending on what it was cut from/to the gas port may need to be opened up a bit. When you cut the barrel you cut the amount of time gas is flowing through the system. This issue will be more apparent in cold weather. So it may have shot great in warm weather but not cold.
I would try the lower first. If that doesn't work you will likely have to open the port.

Also, you might just need to lube it. Ar's don't run well dry.

Sent from my SAMSUNG-SGH-I997 using Tapatalk 2

bigtattoo79 · Dec 8, 2013

gunslinger06 said:
Depending on what it was cut from/to the gas port may need to be opened up a bit. When you cut the barrel you cut the amount of time gas is flowing through the system. This issue will be more apparent in cold weather. So it may have shot great in warm weather but not cold.
I would try the lower first. If that doesn't work you will likely have to open the port.

Also, you might just need to lube it. Ar's don't run well dry.

Sent from my SAMSUNG-SGH-I997 using Tapatalk 2

Well it was pretty cold today.

I lubed the heck outta it but it didn't help.

gunslinger06 · Dec 8, 2013

bigtattoo79 said:
Well it was pretty cold today.

I lubed the heck outta it but it didn't help.

Yeah didn't mean to insult. I just didn't know how experienced you were. Its a common issue.

Try the other lower. You might have a buffer that's too heavy. My guess, without putting hands on it, would be the barrel though usually they won't shortstroke EVERY time.

Sent from my SAMSUNG-SGH-I997 using Tapatalk 2

bigtattoo79 · Dec 8, 2013

gunslinger06 said:
Yeah didn't mean to insult. I just didn't know how experienced you were. Its a common issue.

Try the other lower. You might have a buffer that's too heavy. My guess, without putting hands on it, would be the barrel though usually they won't shortstroke EVERY time.

Sent from my SAMSUNG-SGH-I997 using Tapatalk 2

You didn't insult me at all! I'm thankful for any advice. I didn't know about the cold effecting it more. And I just wanted to point out that I did lube it well.

Thanks Lance

A1 Upper troubles.

The Best online firearms community in Louisiana.

Member Benefits:

Well-Known Member

Stupid is 'posed to hurt

Well-Known Member

Well-Known Member

Please be my friend

Well-Known Member

Well-Known Member

Well-Known Member

Please be my friend

Well-Known Member

Well-Known Member

Well-Known Member

Never go to BR/NO

Please be my friend

Well-Known Member

Well-Known Member

Never go to BR/NO

Well-Known Member

Never go to BR/NO

Well-Known Member

Log in

Forum statistics