PA-10 GEN 3

[Steve_In_29]

I was mostly worried about the spring and whether it was the same as the Sprinco Orange.

I can get the KAC/Sprinco setup from Primary Arms on sale but the KAW setup from Joe Bob's is cheaper overall once shipping/tax is included.

 

Edited November 18, 2021 by Steve_In_29

[98Z5V]

22 hours ago, Steve_In_29 said:

What would changing the buffer/spring do for me?

 

First, I'll tell you that your gas port is undersized, and probably not drilled in the proper location.  Then, they'll just toss and AR-15 gas tube in there, and it'll come up short for what it needs to be.  After that, they used a 3.8oz buffer, which just isn't Enough Ass To Control The Mass...   of a .308 Win round.  They probably just tossed an AR-15 Carbine recoil spring in there, because they don't care.  There's a couple Band-Aids that they do on that Gen 3 gun - they mill two little triangles out of the ears on the lower receiver, so you can't tell when the BCG is striking the lower receiver, because of that weak recoil system.  Second, they put an adjustable gas block on there to "tame it" because it's a .308 Win round.  The truth is - it's not over-gassed, and needs that adjustable gas block.  It's UNDER-gassed, and it's WAY under-recoiled.  Right from the factory.

There's more work to do to that gun to make it right - whether it runs or not, right now.  They ship a shiit-product that works for most of the people, most of the time, with most of the off-the-shelf ammo.  It won't work every single time, though.

Read this when you have the time - I didn't learn this on the internet.  I learned it from building these big things...

 

Edited November 19, 2021 by 98Z5V

[98Z5V]

12 hours ago, Steve_In_29 said:

I was mostly worried about the spring and whether it was the same as the Sprinco Orange.

I can get the KAC/Sprinco setup from Primary Arms on sale but the KAW setup from Joe Bob's is cheaper overall once shipping/tax is included.

 

You could just do it right, and run the Armalite AR-10 Carbine Recoil System that was linked earlier.  That's the proper way to do it, and it's only a few more bucks.  You'll still need to change the gas tube, and drill your gas port.

[DiggerDave]

On 10/20/2020 at 9:36 PM, 98Z5V said:

"Adjustable stock lower" could mean a few things - rifle recoil system with a MagPul PRS stock.  Carbine recoil system with a standard 6-position setup, and a carbine buttstock that slides.  Weird combo for a 20" barrel, but if the recoil system is right, then it doesn't matter what your barrel length or gas system is - as long as gas system and recoil system are balanced.  If it's truly the carbine recoil system...  then... 

You'll also find that the buffer is too light, the receiver extension won't be the right internal depth, and the gas port will be too small.  It probably has an AR15 recoil spring in it.

Just being honest, based on history here with these things.

OK, I'll chime in on this subject. Has PSA listened to their customer base and incorporated design changes in their new Gen 3?

I purchased a complete lower and a separate 20" SS upper in late 2020. It has run well as configured even with a 7" receiver extension and light buffer they ship with

The common issue of too small a gas port size had me curious so I just pulled it down and checked it. Expecting to have to drill it I started sizing and it ate the #44 bit and the #43 with #42 pretty close and a 41 would not go so it looks like they did open up the port but now too big! Guess since they now include an adjustable gas block more must be better.

[98Z5V]

10 minutes ago, DiggerDave said:

OK, I'll chime in on this subject. Has PSA listened to their customer base and incorporated design changes in their new Gen 3?

I purchased a complete lower and a separate 20" SS upper in late 2020. It has run well as configured even with a 7" receiver extension and light buffer they ship with

The common issue of too small a gas port size had me curious so I just pulled it down and checked it. Expecting to have to drill it I started sizing and it ate the #44 bit and the #43 with #42 pretty close and a 41 would not go so it looks like they did open up the port but now too big! Guess since they now include an adjustable gas block more must be better.

 

You have a 20" rifle gas barrel.  What you're quoting is for an 18" midlength gas barrel, which should be 0.080"~0.085".   Your 20" rifle gas barrel should be 0.092"~0.096", to run right.

You have a weak recoil system, because that's WAY cheaper for them to build.  They try to compensate for this with a gas port that's too smal, and commonly an AR15 gas tube that's too short.  The adjustable gas block isn't on there because the gun is overgassed - it's on there becacuse it's under-recoiled.

By the way - PSA used to void your "lifetime warranty" on their own gun, if you put an adjustable gas block on there to "fix" the under-recoiled issues...  

https://littlemachineshop.com/reference/numberdrillsize.php

[DiggerDave]

38 minutes ago, 98Z5V said:

You have a 20" rifle gas barrel.  What you're quoting is for an 18" midlength gas barrel, which should be 0.080"~0.085".   Your 20" rifle gas barrel should be 0.092"~0.096", to run right.

You have a weak recoil system, because that's WAY cheaper for them to build.  They try to compensate for this with a gas port that's too smal, and commonly an AR15 gas tube that's too short.  The adjustable gas block isn't on there because the gun is overgassed - it's on there becacuse it's under-recoiled.

By the way - PSA used to void your "lifetime warranty" on their own gun, if you put an adjustable gas block on there to "fix" the under-recoiled issues...  

https://littlemachineshop.com/reference/numberdrillsize.php

OK thanks, yes rifle length gas system on a 20" bbl. So they got it right on the 20" bbls.?

Yes I know the recoil system is a BIG compromise and will replace it with an Armalite extension and proper weight buffer.

[98Z5V]

Just now, DiggerDave said:

OK thanks, yes rifle length gas system on a 20" bbl. So they got it right on the 20" bbls.?

Yes I know the recoil system is a BIG compromise and will replace it with an Armalite extension and proper weight buffer.

I doubt they got it right.  What's the largest (smallest, numerically) bit that DID clear your gas port?  The 43, or the 42? 

Use the shank end of the bit to check the fit, not the drill end of it...

[DiggerDave]

3 minutes ago, 98Z5V said:

I doubt they got it right.  What's the largest (smallest, numerically) bit that DID clear your gas port?  The 43, or the 42? 

Use the shank end of the bit to check the fit, not the drill end of it...

42 shank would pass 41 is a no go so it is between 0.093 and0.096. I'm guessing by how it felt that it's close to 0.094.

 

[98Z5V]

6 minutes ago, DiggerDave said:

42 shank would pass 41 is a no go so it is between 0.093 and0.096. I'm guessing by how it felt that it's close to 0.094.

 

Well, they got that one borderline right, at the very bare minimum then.  With adjustable gas, if it was mine, I'd straight punch that thing to 0.096", make that 41 clear, and you have no penalty (with adjustable gas).  That way, you know it'll always function.  Once you upgrade that weakass recoil system that they sent you. 

You could skip fixing the wrong recoil system in the gun, and just use your adjustable gas block - but that's just putting the band-aid on the wrong cut...

Edited December 21, 2021 by 98Z5V

[DiggerDave]

1 minute ago, 98Z5V said:

Well, they got that one borderline right, at the very bare minimum then.  With adjustable gas, if it was mine, I'd straight punch that thing to 0.096", make that 41 clear, and you have no penalty (with adjustable gas).  That way, you know it'll always function.  Once you upgrade that weakass recoil system that they sent you. 

Roger that. Much obliged.