XCR Forum banner
1 - 16 of 16 Posts

·
Registered
Joined
·
143 Posts
Discussion Starter · #1 ·
I just received my new complete upper in the mail!!!!!!!!!!! Thanks Terra & Allison!! It was definately worth the wait!!

Got a couple of questions for Terra. The new upper has a barrel bolt that takes a 5/16" allen wrench instead of the usual 1/4" bolt on my other XCR. Are these bolts interchangeable? Is there any benifit of one over the other? I may order another bolt so I won't need to pack two wrenches to the range!

The gas tube can slide back and forth about 1/16". My other XCR does not have this play. Will that hurt anything?
 
G

·
there was a mistake machining this current batch of uppers. the holes had to be drilled a bit larger and a slightly bigger bolt was put in as a result.

I do not know if a loose gas tube will effect anything, but a chat with Alex might enlighten us a bit. let us know what he says.

has this effected accuracy in your gun?

Do you see any gas bleedby that makes it dirty or could effect functioning?
 

·
Registered
Joined
·
5,177 Posts
what kind of movement are you getting from the gas tube? back and forth or side to side? is the male notch on the gas block not meeting into the female notch on the gas tube?


And yes, you got one of the corrective-machined uppers. Functions fine, just bigger bolt.
 

·
Registered
Joined
·
143 Posts
Discussion Starter · #4 ·
Jack A Sol, I just got this upper today, so I have not had a chance to test it out yet to see if the lose gas tube has any effect.

Terra, The gas tube moves back and forth (not side to side).

On different note, while playing around with the upper tonight, I also noticed that if I install my 6.8 conversion kit (from my other rifle) on this new upper, the 6.8 bolt (not the barrel bolt) will not close all the way into battery!? Yet it will close with my 5.56 barrel and bolt.

Terra, What do you recommend?
 

·
Registered
Joined
·
143 Posts
Discussion Starter · #5 ·
The male notch on the gas block just barely touches the female notch on the gas tube.
 

·
Registered
Joined
·
5,177 Posts
Change out carriers. Put the 6.8 bolt into your old carrier and then try that out in the new upper.

Sorry, these things can be tricky without a lower to match them up to.
 

·
Registered
Joined
·
143 Posts
Discussion Starter · #7 ·
What is your take on the male notch on the gas block just barely touching the female notch? Is that anything to worry about??

I'll try swapping carriers too.
 

·
Registered
Joined
·
5,177 Posts
there is supposed to be a ring tapped down in the upper, which pushed to tube up just a little bit. If the upper is missing the ring, that could be the cause...

aw, sheesh. Someone is going to get slapped tomorrow. :duh:
 

·
Registered
Joined
·
702 Posts
I have had my XCR for almost three years and it is an early serial number. My gas tube has always had about 1/16" back and forth play. It has functioned 100% with no FTE or FTF and thousands of rounds through it. It would say the play is normal.

MadDog ;)
 

·
Registered
Joined
·
143 Posts
Discussion Starter · #10 ·
Okay Terra, I just spent some time comparing my other XCR with the new upper. It appears that there is no ring in place to push the gas tube forward. It looks like my old upper has one. I don't think that is the total problem though... When a barrel is seated as far as it will go into the receiver and I tighten the barrel bolt, the barrel is pushed forward about 2/16" causing the play in the gas tube. My other upper does not do this. Could it be that the oversized barrel bolt hole was drilled about 2/16" out of place?

I also tried swapping carriers to address the fact that this upper will not allow the 6.8 bolt to go into battery. It did not help. My other upper will work well with both barrels. I am thinking this particular receiver might be out of spec.

I talked to Allison on the phone today. She said to send it in for a replacement. Is there anyway I can get a "non-corrective machined upper" this time?
 
G

·
my gas tube also moves back and forth about 1/16" and I have the same 5/16 nut as you do. terra shot the shit out of it before she sent it off to me and didnt have any problems after break-in. accuracy was good IIRC (terra?). I dont seee any signs of gas bleed by.

the AK also has some play in it's gas tube when installed properly. this increases reliability and relieves pressure from the barrel which may enhance accuracy.
 

·
Registered
Joined
·
5,177 Posts
I don't think there is really anything wrong with the upper itself, darrell. You do need a ring in the upper, for one. But rather than compromise, I am going to get you a better upper. It might be a week or so from the time I get yours back, but rather than hassle it, we'll just replace it.

Steve has the same kind of upper, but his is fully functional.
 

·
Registered
Joined
·
143 Posts
Discussion Starter · #13 ·
Thanks Terra!!! I really appreciate your help with this!!!! Which address do I send it to? I'll get it in the mail on Monday.

Jak A Sol, I originally guessed that I had about 1/16" of play, but when I actually measured it, it is a little more than 2/16". It is enough that the gas tube can almost rotate. I think the over sized bolt in and of itself is not a problem, but I think something must be a little off on this particular upper. Plus, when I install my 6.8 kit on this receiver, the bolt will not go into battery (Terra, any idea what might cause this?). None of the above happens with my other upper.

In any case, I am just greatful that RA has such nice people working for them!
Happy Halloween!
 

·
Registered
Joined
·
143 Posts
Discussion Starter · #14 ·
Terra, FYI I dropped it off at the UPS store today. Won't actually ship until Monday though. I sent you and Allison an email with the tracking number.
Thanks and have a great weekend!
 

·
Registered
Joined
·
143 Posts
Discussion Starter · #16 ·
Well, they did it again.............

Terra and Allison came thru with shining colors! I got my upper receiver back and everything seems to fit great! (I'll test it out at the range next week). I even told Alex about their excellent customer service! Thanks!!!!!!!!!!!!!
 
1 - 16 of 16 Posts
Top