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Gopher

Continuation of Gopher's issues

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1 hour ago, bfoosh006 said:

And again, "correct" or not ... mine still function fine with a short gas tube.

All I am saying is the short distance from the gas tube into the PSA large frames has made no discernible function issues for me and mine.  So, clearly it is working for all my 18", 20", and 22"uppers and 12.5" I helped my friend build.




98Z5V... I would love to get together and spend hours discussing our collective observations and experiences... I am sure you and I could ramble and chatter over the most odd AR issues .

Same here  - it would be a riot, for sure...  :laffs:

In reference to the stuff I bolded above - your guns are only running because everything else is "right enough." As soon as you toss a gas port in there that's too small, no bueno.  Everything turns to shiit. As soon as you throw a stronger (correct) recoil system in there, again, no bueno.  Lack of gas pressure is fighting a proper (and not weak) recoil system.

It's exactly why I said this, in that other linked thread:

It's come up that the carrier key sits further back on the 308AR than it does on an AR15 - it's in the exact same place from the front of the carrier back to the front of the key, but that 308AR bolt is alot bigger than an AR15 bolt, and when the bolts are seated in the carrier, in the firing position, that key is further back on a 308AR.

That's issue #1.

Next, Armalite vs. DPMS (and AR15) gas systems.  Why Armalite gas tubes are longer than standard AR15 gas tubes (and DPMS_based LR308 parts), I have no idea. Why DPMS uses AR15 gas tube lengths for 308ARs, I have no idea...  However, I DO know that Armalite knows their shiit, and they have a scientific, tested, proven reason for making AR-10 gas tubes longer.  Whatever reason that is, you can know that it's a good one.  Pat Raley could tell us all about it, I'm positive.

That's issue #2.

Next, that carrier key overlaps the end of that protruding gas tube, and it's for an exact distance/measurement.  It's THAT WAY so the bolt carrier receives the proper amount of gas, for the proper amount of time, in order to properly cycle the semi-automatic weapon.  Once that bolt carrier assembly has made enough rearward travel, it disengages from the end of that gas tube, and the remaining gas is discharged directly into the (now open) upper receiver.  It's the excess gas you see coming out of the ejection port when your buddy fires his weapon...

That is issue #3.

Now, that leaves us here - with a gas tube that is NOT the proper length, and it's short by 3/16", that bolt carrier is NOT receiving the proper amount of gas, for the proper amount of time, and it's not fully cycling that bolt carrier assembly with the proper amount of force that it was designed for.  It might cycle, but it's NOT going to cycle as it was designed to do...  THAT cannot be argued.  It's science and math.  Done.

 

It's more than a gas pressure thing,from the power of the round.  It's the timing of the gas system that gets completely out of whack.  You toss on another out-of-spec dimension somewhere else in the complete operating system, and you have a gun that functions like shiit.

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18 minutes ago, 98Z5V said:

Same here  - it would be a riot, for sure...  :laffs:

In reference to the stuff I bolded above - your guns are only running because everything else is "right enough." As soon as you toss a gas port in there that's too small, no bueno.  Everything turns to shiit. As soon as you throw a stronger (correct) recoil system in there, again, no bueno.  Lack of gas pressure is fighting a proper (and not weak) recoil system.

It's exactly why I said this, in that other linked thread:

 

 

Agreed... I would like to know if PSA has changed its "normal" 0versized gas ports... but my April manufactured ones ( rifle length gas ) still had ample gas flow. Enough that I still installed all the fix the " overgassed " issue parts.

And... all the PSA's ran in OEM configuration... and were "overgassed"

What are your thoughts on that "peened" area in Gophers upper ?

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3 minutes ago, bfoosh006 said:

And... all the PSA's ran in OEM configuration... and were "overgassed"

What are your thoughts on that "peened" area in Gophers upper ?

I think people confused "overgassed" with that weakass recoil system, brother, honestly.  Fuk me, that recoil spring I got from Gopher isn't even fit for duty in an AR15, let alone a .308 Win-powered load.  The buffer is too damn light (my saying of "not enough a$s to control the mass"), and the receiver extension has too much internal depth, so your BCG crashed into the ears on your lower receiver.  What a goatfuck of a recoil system.

On that peening, I can't say from pictures.  I need to get that upper in my hands, and Gopher and I will work that out.  I'm gonna fix this upper assembly, and he's gonna have a fully functional rifle.  I will find out what the hell is going on with this thing, and I will fix it. 

I don't think there's a gas leak anywhere - that takes care of itself after about a dozen rounds.  Nothing is ever air-tight when you first build it, gas escapes from the gas block and the gas tube (into the gas block).  Carbon fouling seals that up pretty quick.  I think he's got a gas port issue, and it's too small.  Possibly some other issues.  If I find some machining issues with that upper, I will be posting it here, letting PSA know about it, and getting Josiah/Jamin involved.

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