PA10 GEN 2 Tube Marks

[Bigfoot]

Shot the PA10 for first time.First 20 rounds PMC 147 grain brass.1 FTE on rapid fire.Ran wet next 20 rounds of same ammo.No FTE.

Lube heavy and ran 100 rounds Tula 150 grain FMJ steel.Went ok.

Upon cleaning inspection found the tube damaged at approximately 4&8 o’clock.No wear marks on rear of BCG.

Also notred weapon appears over gased.Is it normal to have a tender shoulder and slight bruising on this platform?Limb saver is on the way.

At times it feels like the buffer spring is slapping/bound in buffer tube.

Buffer 3.24”

Buffer weight.Unknown at this time.

Buffer tube ID.Rear to pin.7 13/16”.7 5/8” at 9 & 12 o’clock.

Spring length 11 1/4”

Spring Coils 29

Spring Diamter .072

Any insight appreciated.

[Matt.Cross]

  On 5/20/2018 at 12:04 PM, Bigfoot said:

Shot the PA10 for first time.First 20 rounds PMC 147 grain brass.1 FTE on rapid fire.Ran wet next 20 rounds of same ammo.No FTE.

Lube heavy and ran 100 rounds Tula 150 grain FMJ steel.Went ok.

Upon cleaning inspection found the tube damaged at approximately 4&8 o’clock.No wear marks on rear of BCG.

Also notred weapon appears over gased.Is it normal to have a tender shoulder and slight bruising on this platform?Limb saver is on the way.

At times it feels like the buffer spring is slapping/bound in buffer tube.

Buffer 3.24”

Buffer weight.Unknown at this time.

Buffer tube ID.Rear to pin.7 13/16”.7 5/8” at 9 & 12 o’clock.

Spring length 11 1/4”

Spring Coils 29

Spring Diamter .072

Any insight appreciated.

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You've got bolt carrier over travel! The good news is that it is not difficult to fix.

[mley1]

Looks like you might need to put a couple quarters in your tube behind the spring. Your bcg is hitting the receiver at the threads. To fix the over gas problem an adjustable gas block is an easy fix. Once you put an adjustable gas block on and get it tuned right your shoulder will stop hurting. On mine I also put a good muzzle brake on it that helped a lot. Shooting it now is about like shooting my AR15's.  Prior to installing the adjustable gas block I was having a few fte. After the gas block and adjusting, zero malfunctions.

I'll mention also that if your buffer is only an H buffer you can help your rifle by putting two more tungsten weights in the buffer. This will make it an H3 buffer, and helps a bit with the functioning of the rifle. I got extra tungsten weights off of ebay.

Edited May 20, 2018 by mley1
add info

[98Z5V]

  On 5/20/2018 at 12:04 PM, Bigfoot said:

 

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The components have the correct dimensions.  The receiver extension isn't screwed all the way into the lower.  You can see that it's set back from the face of the lower - it should be almost flush with it. You'd probably have to notch it to screw it in another turn, though.

Can you get that same pic, with buffer removed?

 

[Bigfoot]

Thanks for responses.

 

98Z5V Here is a pic as requsted.

 

Edited May 20, 2018 by Bigfoot

[98Z5V]

Yep, mark that buffer retainer centerline right there, and notch that thing with a Dremel Chainsaw Sharpening Bit.  You need to take it in another turn, but if you don't notch it, you won't be able to.  You'll have to depress the buffer retainer on that last turn, to get it to rotate past the buffer retainer.

That should help things greatly.

Here's one I had to notch, for the same reason...

Notice that the receiver extension face is almost flush with the face on the lower.  If the receiver extension face protrudes beyond the face of the lower, you won't be able to close the upper on the lower - the back end of the BCG will snag on it, and prevent it from closing.

[Bigfoot]

98Z5V appreciate assistance.Filed notch & screwed tube in one turn.

mley1 ordered tungsten buffer weights from eBay just in case.Thank you.

After file and one turn on buffer tube.Upper closes on lower.

 

 

 

 

Edited May 21, 2018 by Bigfoot

[edgecrusher]

well done!

[jtallen83]

  On 5/21/2018 at 1:02 AM, Bigfoot said:

 

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Looks like it was made that way, guess it was, by you! I had to do the same thing on an Aero buffer tube, I still needed to leave a quarter in the tube though, keep a close eye on it when you first shoot it and add a quarter or two if it still hits.

[98Z5V]

^^^  Yep, what JT said. Measure that internal depth again.  You want 7 5/8" internal depth.  If you've got more than that, stack quarters in the base of the receiver extension and take up that space.  Each quarter is 0.069" thick.

[mley1]

  On 5/20/2018 at 9:46 PM, 98Z5V said:

Yep, mark that buffer retainer centerline right there, and notch that thing with a Dremel Chainsaw Sharpening Bit.  You need to take it in another turn, but if you don't notch it, you won't be able to.  You'll have to depress the buffer retainer on that last turn, to get it to rotate past the buffer retainer.

That should help things greatly.

Here's one I had to notch, for the same reason...

Notice that the receiver extension face is almost flush with the face on the lower.  If the receiver extension face protrudes beyond the face of the lower, you won't be able to close the upper on the lower - the back end of the BCG will snag on it, and prevent it from closing.

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This is something I never thought of doing, and had never heard of until you posted it. Looks like a good permanent solution to a dimension problem. My problem is that I'm so ham handed I'd prolly screw up my buffer tube and end up buying a new one................quarters were easiest for me. I'll never be broke. I'll always have at least 50 cents I can pull out,.....................for half a cup of water. LOL

[Bigfoot]

Cannot edit original post.

Add- Buffer weight is 3.75 oz.

Great ideas by 98Z5V.Started  with chain saw file and finished with round jewelry file.

On a side note.Limbsaver fit mil spec Magpul moe nicely.

[98Z5V]

^^^  That stuff that I posed up above is only a start, and you still need to measure the internal depth of the receiver extension, even if you file and give it another turn. Getting it installed correctly is the first step, and that's what that is above.

AR15 Carbine Receiver extension (and the DPMS-based 308 extension) should have an internal depth of 7.000".  Armalite AR-10 (based) Carbine Receiver Extension should have an internal depth of 7 5/8".  If it's still over that, it's time to stack quarters, or find a tube that's in-spec. 

[Bigfoot]

ID is 7 5/8” at 3,12 & 9 o’clock.

ID is 7 3/4” at 6 o'clock where detent pin is located.

When upper is closed.BCG barley kisses buffer face.

[98Z5V]

3.250" long buffer, right?  That extension is correct for an AR15-sized H3 buffer. 

[GoodByNAair]

I know i'm late to the party. Both my 18 " PA10 and my dads 20'' PA10 did this and both took $.50 to fix. I'm also running an H3 5.4oz buffer, it helps. 

 

I will be getting a H3 for my 7.62x39 next with that and the break it  will be like a mill 5.56.

[98Z5V]

  On 5/23/2018 at 1:48 AM, GoodByNAair said:

I know i'm late to the party. Both my 18 " PA10 and my dads 20'' PA10 did this and both took $.50 to fix. I'm also running an H3 5.4oz buffer, it helps. 

 

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Check both those receiver extensions, too.  Make sure they don't need "modded" to screw in another turn... 

@bfoosh006, try to see if this in an ongoing issue at PSA - let them know about it. Thay can notch their own receiver extensions, in order to fully seat them like they should be, during assembly. This will cut out troubleshooting on message boards, and customer-fixes. And BCGs crashing into lowers.   

Edited May 24, 2018 by 98Z5V

[98Z5V]

@bfoosh006, also let PSA know that I might sound like a dikc, but it's for the better of the company.  I'm harsh, gruff, whatever label that I need.  Armalite doesn't have these issues on their AR-10 Carbine Recoil System. 

Edited May 24, 2018 by 98Z5V

[GoodByNAair]

Will do. Time will be limited for the next few weeks for gun stuff in my life. so i'll update when I can. 

[98Z5V]

  On 5/23/2018 at 1:57 AM, GoodByNAair said:

Will do. Time will be limited for the next few weeks for gun stuff in my life. so i'll update when I can. 

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Right on, brother.  Get to it when you can - just make sure you measure it all out, inspect it, and determine if you need to modify that receiver extension... 

[Bigfoot]

  On 5/22/2018 at 10:00 PM, 98Z5V said:

3.250" long buffer, right?  That extension is correct for an AR15-sized H3 buffer. 

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Yes sir 3.240”.Tungsten weights on the way.Will also have a pocket of quarters ready for next shoot.

[bfoosh006]

  On 5/23/2018 at 1:55 AM, 98Z5V said:

@bfoosh006, also let PSA know that I might sound like a dikc, but it's for the better of the company.  I'm harsh, gruff, whatever label that I need.  Armalite doesn't have these issues on their AR-10 Carbine Recoil System. 

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Agreed... PSA shipped my current production rifles ( both, just got them , last week ) in the correct Armalite style buffer tube, recoil spring and buffer... ( 3.9oz )

I still don't think it is PSA intentions to send out the wrong assm. ... but rather disgruntled personal.. knowingly installing wrong parts.
I have ZERO proof of this... but, come on... this is elementary school stuff.
So some where along the "line" someone is installing the wrong parts... no ifs, and or , buts about it.

I also just posted some of my findings here in the PSA forum concerning the New current production .308 PA10 GenII , and the 6.5CM PA 65 Gen II.

[98Z5V]

  On 5/29/2018 at 6:21 PM, bfoosh006 said:

Agreed... PSA shipped my current production rifles ( both, just got them , last week ) in the correct Armalite style buffer tube, recoil spring and buffer... ( 3.9oz )
 

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Armalite AR-10 Carbine buffer is an H3-weighted buffer at 5.4 oz.

Carbine buffer = 3.0 oz

Carbine H buffer = 3.6 oz

Carbine H2 buffer = 4.6 oz

Carbine H3 buffer = 5.4 oz.

Or, very, very close.  I've seen some that are 0.10 oz in either direction, from those weights.  What you have in yours is more like the H buffer.

[Gopher]

Yeah I am a little confused which is not hard to do since this is new to me.

So it looks like I have a light buffer based off its a H and I have some damage because buffer tube is not sitting right?  BTW, Inside buffer tube length is 7 5/8".

 

[98Z5V]

Really looks like it needs to go in another turn - and it looks like it's already got a little cutout for the retainer - and that's only because it's got that fancy little lip on the lower third of it.

You'll need to cut that notch a little bigger to get it another turn - but you can try it at home, now.

Remove the buffer retainer and it's spring, then screw that extension in another turn - your goal is to see if the side and upper sections protrude PAST the forward edge of the lower receiver (Can't stick out past the "ears" on the lower...).

I swear, it's almost like they're manufacturing this shiit just to test us. It's about turning stupid...