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First Build Problem


Kyblue82

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Ok so I've recently completed my first build.

Alright everyone here is my first build parts list:

Aero Precision M5E1 stripped receiver set w/15" Aero mlok rail

Aero lpk

Hexmag pistol grip

Aero .308 carbine buffer kit

Magpul ACS-L stock

Faxon 18" rifle length medium contour barrel

Gamma 762 muzzle device

YHM gas block

Spikes gas tube

Athlon 1-4x24 scope

Everything went smooth with the build process. Took it to the farm and was ready for the break in. I took advice from posts I had read and used mobile 1 and got everything sloppy. I loaded one round into the mag, chambered the round and fired. The bcg locked back on an empty mag every time. Then things went to crap. I'm getting bolt over base malfunctions, it's totally random, doesn't matter if the round is getting fed from right or left side. I have 2, 25 round pmags. I have tried multiple types of ammo, including different manufacturers, different grain, 7.62x51, it happens with everything. I received an email from Faxon saying there was a recall on the barrel I had so I thought that might be the problem, sent in the old, installed the new one, still happening. I don't know where to go from here. Any insight would be greatly appreciated and I'll try to answer questions to the best of my ability. Thank you

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What other mags have you tried?...

2 x 25rd PMags is what I'm seeing.

What Spike's gas tube?  Details on it, though it's not the issue.  Exact dimensions will help.  Length.

Take a pic and post it, of the gas tube in the upper receiver. Remove BCG, just a pic of how far the gas tube sits into the upper...

 

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This might all be the mag catch, too.

Bolt over base usually means the mag spring is too strong, and is shoving rounds up, on top of the bolt, before it can go into battery... They're a fucker to clear.

Edited by 98Z5V
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Looks like tube is about 15" best I can tell. Here's a few pics that might help.

image.thumb.png.9ff381ca3dced371ab2cd4e6859e3618.pngimage.thumb.jpeg.5275cf229589acd81b3cc86a836141ba.jpegimage.thumb.jpeg.698d956188f394dae1fde1527b28ae00.jpegimage.thumb.jpeg.64e02ace480cf3cbcab02021879698e7.jpeg

yes, yes I know it's dirty than you know what but I haven't cleaned it since I added a quart of motor oil to it this last time. I don't always get to do, what I want to do, when I want to do it, when you got 4 critters running like a bunch of crazed animals, lol! As far as the mag catch goes, I used the one that came with the Aero lpk because it was supposedly longer or something but I could have tighten that thing in until it was below surface of the receiver. 

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Its short , some have had no issues with Carbine Gas systems with a Gas Tube protrusion like that , but Rifle length seems not to like it . As said above Get the Armalite AR 10 Rifle length Gas Tube . Fulton Armory has them also . Damn 98 , we sure are seeing a lot of this lately , you would think Faxon would specify an Armalite Gas tube is needed .

DSCN2514.thumb.JPG.0839f961fd86b6c0f320e89090facce9.JPG

Edited by survivalshop
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DPMS LR 308 Gas Tube & /AR 15/16M4

 

  Pistol             6-5/8

  Carbine          9-3/4

  Mid-Length  11-3/4

  Rifle             15-1/4

 

 

 

 

Armalite lengths,

Rifle ( 308 ) ----- 15.5 "

Mid length Carbine ( 308 )--12 1/16"

super SASS Carbine ( 308 )--11"

Super SASS< Rife (308 )   ?

Mid ,( 223 )------------------ 11 3/4"

Carbine ( 223) --------------- 9 3/4 "

Rifle ( 223 ) ------------------- 15 3/16"

 National Match---------------  ?

 
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2 minutes ago, survivalshop said:

 Damn 98 , we sure are seeing a lot of this lately , you would think Faxon would specify an Armalite Gas tube is needed .

 

I'm starting to wonder why they DON'T specify it, brother... 

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16 minutes ago, Kyblue82 said:

Awwwe...it says on their website on the specs for that barrel, beside barrel extension, dpms compatible, that's probably why I didn't look into gas tube length, I saw that and wrongfully assumed dpms everything for it. 

Not YOUR fault at all.  Not even, in the least.  We are seeing this more and more here.  It's on the barrel manufacturers.

@FaxonNathan  - this is on you guys, man.  What's going on with Armalite gas port lengths and DPMS-spec'd barrels?...  That's comparing apples to hammers, and not telling customers about it...  Needs fixed in the barrel description on the website, or the gas port length needs to be changed to a real DPMS-based gas port length, or customers are screwed. 

And WE are screwed, here, fixing shiit...

I love you guys, but come on...  in the Large Frame ARs, details are EVERYTHING. Like, ALL of it... 

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36 minutes ago, Kyblue82 said:

Thanks, i'll defenitely look into that. So it's too short and not fully blowing the bcg back far enough? Or what?

We started to get WAY into it in this thread right here - I have no idea how we're going to peel back the tech data out of that thread, and make a new tech thread from it.  Shiit got way deep...

 

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Gents-

Our thanks for the heads-up on this thread. We're happy to help, but my posting will be limited to this one until Tuesday. Trying to take a few days off after whirlwind travel. 

As documented on this forum, Faxon changed its gas port lengths approximately two years ago. We went from true "DPMS" specification to extending 1/4" further as customers reported being upset with the inability to use non-free floated systems like FSBs and standard M16 handguards. True DPMS specification is unique to them for the aftermarket non-free float compatibility. We are not yet either true "Armalite" either as we extended .250" versus the .325" needed in some cases. We did this to use standard AR-15 tubes. 

Prior to this change, Faxon tested, extensively,  the change in gas port / gas tube length for function. So long as the tube has a good seal on the key, the overlap is largely superfluous. We actually recommend using standard "AR-15" tubes as they work for everything we have ever tested. Our guns in-house use standard Ar-15 tubes. 

In the case of this particular customer, my personal opinion on the issue is that there is not an issue with the gas tube length. For the weapon to work for a period and for the function to degrade indicates other potential issues, which in our experience is the gas block/tube, BCG, or buffer system. 

OP - please feel free to PM and/or e-mail me and I will help with troubleshooting. We are 100% committed to getting your weapon up and running and will bring it back and troubleshoot in-house if needed. 

Thank you, gentleman, and look forward to picking this back up on Tuesday. 

 

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No disrespect to Faxon ment but get the Armalite rifle length tube and try it, it is a relatively cheap part. It may be some other detail in the gas system but we have seen this cure the problem numerous times and your picture looks just like the others that were fixed with the little extra gas tube length.

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4 minutes ago, jtallen83 said:

No disrespect to Faxon ment but get the Armalite rifle length tube and try it, it is a relatively cheap part.

^^^^That right there! You did good getting the Faxon barrel, their customer service is great and as you see, they have a presence on the forum here and WILL help you sort it out if we can't!

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I've got nothing but great things to say about Faxon. They were awesome to deal with when we were going thru this recall stuff. If I sent an email, they got back to me asap. Even threw in a free muzzle device for the troubles. I've heard a few of the guys from Faxon speak on some podcast and they just seem like good people. Top notch customer service!

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    Thanks Faxon for posting an answer , you seem to be always there for your Customers & I for one , appreciate it ,as I'm sure other do here also ,

     but using the same logic of your answer as to the system working at first , goes both ways , if the system worked with the the Gas system & Buffer system at first , the same thing can be said , thats its something else .

    I agree the Gas Block can be miss aligned or loose & not letting proper gas signature or the Buffer system can be wrong & should be checked  ( we have seen our share of the wrong Buffer Springs & Buffers from reputable Manufacturers )

    The changing of the Gas Tube to an Armalite Gas length of 15.5" is a logical & inexpensive step in assuring the proper timing of the Action . When we see the Gas Tube protrusion at such a minimal amount, but as said , some work in that position with 308 Carbine gas systems , the determining factor there is the vastly increased gas signature of the Carbine system  .

     We have found here that because there are no standards for large frame AR components , that you can't compare one to another when you have issues , the seating in or breaking in of Components of these Rifles can change after a few testing rounds fired .

    I do know for the most part, through experience, that the Gas Tube Protrusion into the Upper Receiver is a determining factor in proper operation of the Action or at the very least can be eliminated from a potential issue . 

   Your Company changing to a different Gas Port location then the ones already in existence , AR 10 & DPMS LR308 ,Rifle length gas system, is another step in the wrong direction in standardization of large frame AR's , Though it may make sense for those who use certain components , it is just another change to make things potentially proprietary . IMO 

     The photo I posted above is of a DPMS LR308 with a Kreiger/Criterion Barrel from Fulton Armory ( before they changed to the present Gas Port configuration on their Barrels , I have two rifles with them in the exact same position , a 16" & a 20"  ) with AR 15 Rifle length Gas Tubes .

Fulton Armory now recommends & sells AR 10 Rifle length Gas Tubes for their Barrels , probably because they made specification changes to the Barrels made for them.

 From the Fulton Armory web sight;

 Approximately .325" longer then AR-15 tube, for use for FA 308 & 6.5 Barrels. Will also work on Armalite AR-10. 

 

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Ok so got the gas tube swapped out to the armalite tube and still no change. I can't get thru 5 rounds without a jam. Also had a few cases that did not fully eject, they bounced back into the receiver, that's never happened before. Not sure where to go from here. Buffer or spring? Mag catch? Trying some different mags? 

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Kyblue         you said you bought an aero car 308 buffer kit....right?  So lets check on the other end of the gas system..

you are gonna measure the buffer tube itself  7"     count the coils on the buffer spring and be sure its also the right length

well lemme just post up these pics on what you should have  ...if you have the wrong spring ,buffer, or buffer tube ...that would be fubar      Wash

20160301_181825.jpg

002.JPG

 

 

001.JPG

Edited by washguy
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