PA10 Nitrated 18", NB BCG, Gen 2 observations...

[survivalshop]

  Barrel has to be installed & Barrel Nut Torqued to spec's before you can check Head Space , with a dry bolt & Barrel extension locking lugs.

From Foreter Web Sight 

"Three lengths of Headspace Gages are available per caliber:

GO length — This checks the rifle to see that the chamber will accept the cartridges made to maximum SAAMI specifications.

NO-GO length — This is used by most gunsmiths as a maximum headspace gage when chambering a rifle’s headspace dimension. If a rifle closes on a NO-GO gage, it may have excessive headspace. If a rifle closes on a NO-GO gage, it may still be within the SAAMI Rifle Chamber tolerance. Next, it should be checked with a FIELD gage.

FIELD length — If a rifle closes on a FIELD length gage, its chamber is dangerously close to, or longer than, SAAMI’s specified maximum chamber size. This is the longest of the three gage lengths. "

 From Criterions Sight ;

 

"Please note that although many .308 AR bolt manufacturers advertise their bolt as compatible with DPMS pattern .308 AR rifles, lug and bolt face tolerances often vary widely between different manufacturers (as opposed to the AR-15, where there is a uniform industry standard). Criterion barrels are gauged at the factory with Fulton Armory .308 AR bolts. We have also had success in demo rifle testing with bolts from DPMS and JP Enterprises. If you have any questions regarding bolt compatibility, please email us at contact@criterionbarrels.com."

[survivalshop]

1 hour ago, Boot_Scraper said:

Seriously though, the .308 has way more gas than it needs. The mid length gas system on the PA-10 compounds it. The adjustable gas blocks allow you to tune it to where it uses just what it needs to operate properly. Makes for lighter felt recoil and it's easier on the moving parts. Or so I've read. 

 This is why I only use Rifle Length Gas systems on my 308AR's , My 16" HB by Criterion has a Rifle length system & is not over gassed , it has a 308 Kick or recoil , but its more of a shove . 

[bfoosh006]

4 hours ago, hillpitcher2006 said:

This is a very informative thread. I am picking up a PSA Gen2 complete lower this afternoon and will being building around it, and I've picked up a lot of interesting bits of information from your notes.

Can you reiterate why you installed an adjustable gas block?

My main reason for the adjustable gas block was the cyclic action of the PSA... it was needlessly over zealous.

I do think the PA10 GenII has a "industry standard" gas port size... but also believe it is slightly bigger ( more gassed ) then needed or wanted... ( at least by me )

USGI weapons are usually overgassed so they will work in the most awful conditions possible.... full of muck, no lube or cleaning for ages.. etc... so they really want the firearm to cyclic "no matter what".

My .308 AR will most likely never see severe conditions like that ( I could always increase the gas anyhow.. ).

So by using the adjustable gas block, I can limit the available gas volume, and have a fully functioning , softer shooting, easier on the brass and rifle parts, stay on target quicker, more pleasurable .308 AR to shoot.

The difference between the OEM non-adjustable and the SLR adjustable gas block configured rifle was "night and day"...

The brass cases were not showing signs of violent, still under high pressure extraction after tuning the SLR... ( 5-6 clicks of 12 available )

IMHO, the mere fact that the PA10 GenII will function 100% with , lets just say for the sake of argument, half of the gas of the OEM configuration tells me I did the right thing....remember I am even running a Tubbs .308 Flatwire and a 9.3oz HEAVY rifle buffer with that setting....

Out of all the changes I have done to the firearm... the adjustable gas block was by far the best improvement.

To quote someone on another forum... It changed the firing of the rifle from "Linda Blair" in the Exorcist movie to a calm, controllable Winnie the Pooh.

 

I whole heartedly recommend the SLR Adjustable gas block... so much so that I bought 2 more shortly after see how much improvement it does.

Much better then just adding weight to the buffer, and or more powerful recoil springs... frankly, if I did it over again... I would skip the KAK 9.3oz buffer completely... and use the adjustable gas block to control the OEM over zealous recoil.

 

On a side note....a lot of people say the recoil isn't bad.... I am 250lbs 6' and can certainly handle the OEM recoil... but have never understood why I should have to ? IE... if I could make your .308 AR recoil like a much smaller caliber, why wouldn't someone want that ?...

The benefits of the SLR ( a quality adjustable gas block ) far out weigh the added cost.... you will enjoy every aspect of a adjustable gas block.

If anyone orders one from SLR... be sure to consider the 2mm Bondhus wrench they sell and the barrel dimpling jig ( used mine on 4 barrels now ) it took all the guess work out of the install.

 

I hope that answered your question ... if not , feel free to ask more.

 

[bfoosh006]

2 hours ago, survivalshop said:

  Barrel has to be installed & Barrel Nut Torqued to spec's before you can check Head Space , with a dry bolt & Barrel extension locking lugs.

From Foreter Web Sight 

"Three lengths of Headspace Gages are available per caliber:

GO length — This checks the rifle to see that the chamber will accept the cartridges made to maximum SAAMI specifications.

NO-GO length — This is used by most gunsmiths as a maximum headspace gage when chambering a rifle’s headspace dimension. If a rifle closes on a NO-GO gage, it may have excessive headspace. If a rifle closes on a NO-GO gage, it may still be within the SAAMI Rifle Chamber tolerance. Next, it should be checked with a FIELD gage.

FIELD length — If a rifle closes on a FIELD length gage, its chamber is dangerously close to, or longer than, SAAMI’s specified maximum chamber size. This is the longest of the three gage lengths. "

 From Criterions Sight ;

 

"Please note that although many .308 AR bolt manufacturers advertise their bolt as compatible with DPMS pattern .308 AR rifles, lug and bolt face tolerances often vary widely between different manufacturers (as opposed to the AR-15, where there is a uniform industry standard). Criterion barrels are gauged at the factory with Fulton Armory .308 AR bolts. We have also had success in demo rifle testing with bolts from DPMS and JP Enterprises. If you have any questions regarding bolt compatibility, please email us at contact@criterionbarrels.com."

Thank You ! .....I will be checking headspace again after torqueing the barrel ... I was just gettin' antsy !!

And as for compatibility ... I e-mailed Criterion weeks ago and they said it should be GTG... I gave them the specific model and make of the rifle.

[bfoosh006]

2 hours ago, survivalshop said:

 This is why I only use Rifle Length Gas systems on my 308AR's , My 16" HB by Criterion has a Rifle length system & is not over gassed , it has a 308 Kick or recoil , but its more of a shove . 

I am in complete agreement about longer length gas systems.... tapping the gas, further down the barrel will always result in a "softer" shooting AR.

If the rifle length version of the PSA had been in stock when I ordered it... I most certainly would have bought that one.

[bfoosh006]

hillpitcher2006 ..... this link has some good input as well...

http://bulletin.accurateshooter.com/2015/05/what-makes-an-ar-accurate-whitley-offers-answers/

"9. Gas Port Tuning: You want to avoid over-porting the gas port. Being over-gassed makes the gas system pressure up earlier and more aggressively. This causes more impulse, and increases forces and vibration affecting the top end and the barrel. Tune the gas port to give the amount of pressure needed to function properly and adequately but no more."

[survivalshop]

    I have also noticed through the years that, some manufacturers NIB Bolts can be tight when new  , because of variances in the coating & not seated to the Barrels Extension & will show funny HS readings . 

  

   

[bfoosh006]

I am no longer a "fan" of NiB bolts... I had never considered the coating aspect.

I have numerous other BCG's in NiB, and haven't had any issues, but IMHO.... it does seem like just a bad idea using a coating in such an important area.

[bubbas4570]

On 09/06/2017 at 4:27 PM, survivalshop said:

 This is why I only use Rifle Length Gas systems on my 308AR's , My 16" HB by Criterion has a Rifle length system & is not over gassed , it has a 308 Kick or recoil , but its more of a shove . 

I stumbled into this truth without really knowing it, and have not regretted my rifle length gas system at all from day one.

And for what it is worth, this holds true even on the smaller brother....AR15.....if the gas system is done correctly.

[bfoosh006]

I installed the Criterion barrel today as per Criterions video, used the Loctite 609, lubed the barrel nut with anti seize, torqued it to 50 ft/lbs , Blue Loctited the gas block screws and torqued to SLR spec.

I then checked the headspace, with the ejector and extractor removed from the bolt.... closed on a "Go" gage and would not close on a "No Go" gage... even with a little nudge / pressure on the BCG assist......( BTW... the SS PSA upper with the OEM barrel was the same )

With the hammer removed , I hand cycled various .308 and 7.62x51 ( 10 different, 5 of each cal.) brands through it , each brand from a fully loaded 20rd mag, all fed and extracted fine... except the 2016 MEN.. 2 of those 20rds were snug extracting... and the bolt went fully into battery.

Are those two rds something to be concerned about ?.... I think I will open another couple of 20rd boxes, hand cycle them and see if it happens again.

 

As per Criterions webpage..." These barrels feature an M4 barrel extension and M118 LR match chamber compatible with both 7.62x51 NATO and .308 Win ammunition. "

Here is the explanation on the "M118LR Match Chamber".... https://sierrabulletsblog.com/2017/06/13/the-m118-lr-chamber-the-223-wylde-of-the-308-ar-world/ ...it is similar to a .223 Wylde chamber design.... I feel comfortable with the M118 LR match chamber.

I will measure the neck diameter on the MEN ammo and compare it to the other rounds...

I would like to test fire it this weekend.

Edited September 8, 2017 by bfoosh006

[survivalshop]

   Once the Bolt seats with the Barrels locking Lugs , it should loosen up , so to speak . Feeding & extracting certain live ammo may have issues extracting on a new build , shouldn't have any issues with the Action when the ammo you feed is fired . Keep it well lubed for the first hundred rounds or so .

  Criterion is my main brand of Barrels for the 308AR , that chamber works very well indeed .

[bfoosh006]

3 hours ago, survivalshop said:

   Once the Bolt seats with the Barrels locking Lugs , it should loosen up , so to speak . Feeding & extracting certain live ammo may have issues extracting on a new build , shouldn't have any issues with the Action when the ammo you feed is fired . Keep it well lubed for the first hundred rounds or so .

  Criterion is my main brand of Barrels for the 308AR , that chamber works very well indeed .

Thank you.

With no mil-spec I was kind of concerned...( parts fitting wise )  but you are right.

[bfoosh006]

Before I forget...

I need to thank everyone here for all their help !!

Thanks Guys !!

[Boot_Scraper]

A lot of folks will be owing you thanks @bfoosh006. Damn thorough ammo testing you did. You might even be qualified as the resident PA-10 guru. Good on you! 

[bfoosh006]

So I received the IMI 20rd mag and the C-Products 20rd mag....

The IMI is GTG, 100% function, drops free loaded and unloaded, holds all 20rds, has just the right spring pressure.... and is OD Green.. ;)

The C Products is... rough cycling almost like it was binding with the BCG holds only 19rds if you want it to seat in the PSA PA10, doesn't drop free at all, the follower looks like something I whittled out of plastic, is NOT anti tilt .. and frankly looks like it uses a M14 mag spring, seriously....I can't say I will buy more C-Products mags.

 

Edited September 9, 2017 by bfoosh006

[mley1]

Bfoosh006, thanks for posting all of your work with the PA10. It's been very informative so far. I purchased an upper and lower also, the ss 18" mlock one. The lower has the EPT trigger. I shot the rifle yesterday. It did ok with Remington Core Lokt 150grn ammo, and Monarch 147fmj. I was getting sub 2 moa, with the Remington stuff going close to 1 moa. I think the rifle can do better with a better trigger. Plus, I think I'll look at putting on an adjustable gas block.

I'm just a hobby shooter though, and not a gunsmith type of guy. So, I doubt I'll be grinding on the barrel nut, or changing barrels. Maybe someday, but for now I'll tackle small stuff, and shot the snot out of it. I really do appreciate you posting up about the PA10. In fact, it's one reason I got mine. You sure can't beat the price on the PA10's.

[survivalshop]

21 hours ago, bfoosh006 said:

So I received the IMI 20rd mag and the C-Products 20rd mag....

The IMI is GTG, 100% function, drops free loaded and unloaded, holds all 20rds, has just the right spring pressure.... and is OD Green.. ;)

The C Products is... rough cycling almost like it was binding with the BCG holds only 19rds if you want it to seat in the PSA PA10, doesn't drop free at all, the follower looks like something I whittled out of plastic, is NOT anti tilt .. and frankly looks like it uses a M14 mag spring, seriously....I can't say I will buy more C-Products mags.

 

  Evidently a new version of the CProducts Mag . after they were sold or bought out . My original CProducts mags are top notch.  I have almost twenty of them ,some of them are still in original wrappers . 

[bfoosh006]

13 hours ago, mley1 said:

Bfoosh006, thanks for posting all of your work with the PA10. It's been very informative so far. I purchased an upper and lower also, the ss 18" mlock one. The lower has the EPT trigger. I shot the rifle yesterday. It did ok with Remington Core Lokt 150grn ammo, and Monarch 147fmj. I was getting sub 2 moa, with the Remington stuff going close to 1 moa. I think the rifle can do better with a better trigger. Plus, I think I'll look at putting on an adjustable gas block.

I'm just a hobby shooter though, and not a gunsmith type of guy. So, I doubt I'll be grinding on the barrel nut, or changing barrels. Maybe someday, but for now I'll tackle small stuff, and shot the snot out of it. I really do appreciate you posting up about the PA10. In fact, it's one reason I got mine. You sure can't beat the price on the PA10's.

 

Just so you know....I know that if I can do it... you can do it.  It truly was that easy, especially if you are mechanically minded.

Even changing the barrel was ( with the right tools ) far easier then I thought it would be. ( Thank God.. )

As for the Adj. gas block... buy a good one and get the dimpling jig, drill gently, and re-watch the SLR install video... numerous times... Lol ( the whole measure twice, cut once thing )

I am glad you are enjoying your bargain rifle.

[bfoosh006]

12 hours ago, survivalshop said:

  Evidently a new version of the CProducts Mag . after they were sold or bought out . My original CProducts mags are top notch.  I have almost twenty of them ,some of them are still in original wrappers . 

I would be very interested in seeing photo's of your C-Products... I forgot to mention, mine appeared to be painted ?!..... a fairly rough surface coating. Nothing like any of the other mags.

[bfoosh006]

As for the testing of the new Criterion barrel, a much more detailed "report" is coming.... but, to cut to the chase, it shot most everything better and I couldn't be happier. No problems at all with the Criterion barrel.

I was at the range from 08:00 - 15:30... fired 100's of rounds, and still got nice, predictable small 10rd groups from its favorite ammo at the end of the day.... with no cleaning at the range at all... the rifle ran 100%.

I fired all the different types of .308 / 7.62x51 I had with me.... I am guessing around 30-40 different rounds. 20rd or 10 round groups.

The Lancers with their stiff springs ( probably not helped by the gas block settings ) caused sluggish feeding.... but all the other mags ran like champs... especially the P-Mags, D&H,  and the IMI.

One other brief highlight was the ZQI ammo no longer shots like a 25yd duckbilled buckshot pattern.... it is not a small group... but it is better.

 

Also, while I am confident the new Criterion barrel helped with the group flyer issues... I can't help but wonder if trueing the receiver face and using the Loctite 609 helped with flyers.... I could see if I messed up the shot.

I started realizing that the "flyers" were a result of me, more often than not, because of my poor bench skills....IE, not maintaining proper rifle holding skills.

I guess what I am saying is.... true up your receiver faces and use the Loctite 609... I will even pull apart the 18"  SS upper and do the same thing to it.

 

I seriously mean it when I say thanks for all the help from this forum and from all you guys... you all helped instill confidence and offered help with a helpful demeanor, something that lacks at other forums sometimes... no one here ever looked down on the lowly PSA PA10 GenII.

After some morning coffee and such, I will start photographing and reporting.

[survivalshop]

47 minutes ago, bfoosh006 said:

I would be very interested in seeing photo's of your C-Products... I forgot to mention, mine appeared to be painted ?!..... a fairly rough surface coating. Nothing like any of the other mags.

  They are made of Stainless Steel with some kind of paint or something & with use it does come off , as you can see in the Photos blow of a well used Test CP mag, probably has 1K or more rounds through it with multiple 308AR's .

New in the wrapper 

Opened new one 

 one on the right has had a lot of rounds trough it .

[bfoosh006]

Appears to be the same follower... mine came in a much heavier plastic bag , and I can see from your photos mine is a lot rougher surfaced.

Here are some photos, along side a M14/ M1A spring as well... and next to the IMI spring.

Please pardon the Dri-Film lube ( whiteish powder ) on the various mag parts.

[bfoosh006]

IMI 20rd AR10 mag photos...nice thick "rubber" base, smooth positive spring action....easy to take apart, seats easily holds all 20rds, fed and functioned 100%

Might be 2nd or 3rd favorite mag... 1st P-Mag, then D&H or IMI... D&H is 100% GTG and is slick sided, to in and out of mag pouches is very easy.

Ignore the whit powdery look... that is just a Dri-film lube.

And the sprng to the left is from the C-Products mag.

 

Edited September 10, 2017 by bfoosh006

[bfoosh006]

New Criterion Barrel shooting results...

First off, the barrel was 100% GTG in all aspects... no issues with its performance, or its install, as a matter of fact I couldn't be happier with it. The online Criterion Barrel install video is excellent and I installed it just like it shows. ( Video # 3 )

I allowed the Loctite 609 about 35+ hrs to dry... prior to shooting.

http://criterionbarrels.com/media/videos/accurizing-the-ar-15-video-series

Kudos to Criterion barrels for a those videos.

I do think the trueing of the receiver face and the Loctite 609 are important, and easy to do, if you have the barrel off.

I suspect Criterions knows what they are doing , ;) Lol ... and the benefits are less flyers and more consistent group sizes.

I could tell when I was screwing up a group.... and really couldn't fault the PA10 GII for those flyers.

 

Here are the first groups of the day.. ( I did fire 6 rounds to get on target )

 

1st photo, FGMM 168gr, 6rds

2nd photo,  FGMM 168gr, 5rds or 6 ?.. I don't remember, I was to excited to try , more ammo.

3rd photo, 20rds BH 168gr Moly coated

4th photo, 20rds Fed. M118LR, happy about this one because I got a great deal on these from PSA ( $300 / 500rds. ..way back when )

5th photo, 20rds rapid fire 168gr FGMM... most of them went into that ragged hole !!

6th photo, 10rds Atomic 168gr Nosler

7th photo, 10rds Maylaisan ball

8th photo 20rds 2016 MEN ball

Edited September 10, 2017 by bfoosh006

[bfoosh006]

2nd Target results....

 

1st photo, that gawd awful ZQI...19rds shown, 20 fired... the first was so off my zero.. I had to find it. Much better performance then before... but still kind .. well, sucks.

2nd photo, 8rds more 168gr FGMM , I was curious if my grouping had shifted after the first ZQI shot... so this was of the fly.

3rd photo, 20rds Fed. AE 168gr M1A

4th photo, 10rds Winc. 147gr White Box ball

5th photo, 16rds '83 Hirt. ball, boxer primed