PSA PA10 (308) Experiment

[Gustav7]

"Carriers hitting the lower ears on the receiver due to the same issues."

FWIW, That actually has a lot to do with how the carrier is cut at those contact areas as well, some of the various brand carriers used, have a sharp corner there, other brand carriers are recessed ( ? ) more rounded area there.
PSA has used both style BCG's , and frankly, the PSA fix worked quite well. Simple and effective.

I would like to see the difference in a Aero Precision 308 DPMS pattern carbine recoil spring and a PSA one , and I am pretty sure Aero uses the same 2.5" buffer weight of 3.8oz.
I wonder if the Aero and PSA carbine recoil springs are made by the same company, to the same spec.

I am glad to see the Armalite buffer tube is smoother inside, since it costs darn near twice as much, and it is good to see the price isn't just for the name.
I have bought other "name brand" buffer tubes looking for a smooth interior, and quite a few were dubious inside, I could feel the ridges, with my finger tip ! So good to know Armalite is another smooth one.

Also and another FWIW, PSA did at one point use the same Vltor / Armalite length buffer tube and 3.25" buffer ... but for whatever reason they abandoned it.
Probably a cost saving measure, just like DPMS and Aero did.

BTW, did Armalite quit selling parts on their webpage ? Sure seems odd I don't see any on there. I know they used to.

I haven't heard of any PSA buffer tube failing, and again ( FWIW ) mine have run many thousands of rounds.
Then again I do run a 5.3oz 2.5" and the Tubbs with an adj GB.

So no meaningful input on the PSA recoil spring, since I changed mine soon after buying mine, just to slow the bolt unlocking so soon. I wish I had just moved to a Adj GB from the get go, Lol

I also see the PSA tube is made from 7075, ( GI spec material ) and not some cheaper material. ( Just went and looked )

I'd bet 6061 would work, but... I would prefer 7075.

I guess I haven't noticed, but is the PSA drain hole really that much smaller then the Armalites ?

"This isnt just a guess, but also isn't verified, but some guys think, and rightly so, that PSA has those bored low on the bottom side to avoid carrier tilt issues."

Are you saying PSA might have a carrier tilt issue ? That is the first time I have heard that.
Would that apply to the AR15 model as well ? It is the same buffer tube.

Where did you hear this ?

I'll measure my buffer tubes, I can't say I have ever noticed any of them being off center, both on AR15's and PA10's

Anyhow, thanks for the updates

It was always told to me that it was a cover up for not adhering to proper design. A lot of this info is form 308AR forum, as there are a few guys over there that specialize in large frame, now that being said, one of them reeeeally hates PSA and not because they're cheap. Supposedly a rep from PSA was on that forum and a few guys went out of their way to help them understand the simple fixes they needed to employ to get the rifles up to par, and they never listened. My BCG in this rifle has plenty of room in that area, even without the cuts, so I'm not worried.

I have no doubt that your buffer tube is running solid, although I'm positive your buffer and gas upgrades have helped. After inspecting and feeling the PSA buffer, I'm just not confident in it. I may be wrong, but I'm already set on using the Armalite one anyways. My main concern is no matter how you adjust the gas block, keeping the bolt locked up a little longer and not having such a violent unlock/extract phase is a positive in my eyes, especially when you get into suppressor use.

The carrier tilt got mentioned over on 308AR, but it was from a few years ago, so it may have been Gen1/Gen2 timeframe. As raggedy as the stock buffer system is, it ran well today. (see my new update)

 

[Gustav7]

***UPDATE***​

Got the lower in today and assembled it. Lower looked very clean, no issues I could see. Looked like any other quality "value" lower. Everything went together just fine with the LPK. I greased up the trigger kit and honestly its not too bad. I've had wayyyy worse "milspec" triggers out of the bag. I believe this is the milspec Nickel Boron trigger kit.

The weird shit started with the buffer tube assembly. The tube they send has a little U notch cut into the threaded area of the buffer tube. I was always taught to run the buffer tube until it is flush with the internal receiver wall, and has more bite on the buffer retaining pin. So thats what I did, and the notch fits perfectly around the buffer pin. That did not end up working out. The rear of the carrier was hitting the tiny portion of the buffer tube that was just a hair past the receiver wall. It may it hard to close and open the upper onto the lower and felt off when you charged it.

So I took the castle nut back off and unscrewed the buffer tube one rotation and tried again. That worked and everything went together ok. However, the short buffer and backed off buffer tube, makes the buffer a little off balance and the carrier hits it when you close the upper onto the lower. I was worried backing it off might push the carrier closer to the receiver wall, but there is ~1/8" of space.

I got her all together and took out 4 mags of ammo. 2 mags were some remanufactured "M80", which I knew is sort of low power, and some Korean surplus that has some serious zip to it. Very good ammo, but feels/shoots on the high end of 7.62 ammo. Ran a little over a 100rds without a single hiccup. I can understand why PSA went to the AGB's, and I will say, it was probably a good idea they did, especially for the average owner of a PA10 who doesn't get into them like someone on here might. I set the AGB to what the card recommended. 17 "clicks" in from zero for .308 Winchester. Wayyyy over gassed. Even the reman'ed M80 was spitting hard at 2 o'clock, and the Korean surplus was at the 1 o'clock and erratically bouncing around.

I walked back to my shop (200yd range in my backyard), and adjusted the gas block 5 clicks toward zero. Ran half a mag of the M80 and it wouldn't cycle, but just barely. Went two clicks back open and was able to run both the M80 and the Korean hot surplus just fine. Both brands were a nice 3 oclock pattern in a smaller pile. Ran 3 rounds of PPU 168 BTHP that I had laying around and same thing, same pile.

I got the RT-6 field zero'ed and clanged some 66% IPSC steel at 100yds. Going to try and hit a range day at our club next week if its nice and try to do some of the accuracy testing. I've got some Federal Berger 168's, 175 SMK's, Fusion 150's, and M118. I'll most likely just go ahead and put the Armalite buffer system on now. Stock kit ran fine, but I'd like to see how the nicer setup effects it at all.

 

[BCP]

Looks normal to me. Might be a good candidate if you wanted to cut down the barrel and pin it.

 

[mtrmn]

***UPDATE***​

Got the lower in today and assembled it. Lower looked very clean, no issues I could see. Looked like any other quality "value" lower. Everything went together just fine with the LPK. I greased up the trigger kit and honestly its not too bad. I've had wayyyy worse "milspec" triggers out of the bag. I believe this is the milspec Nickel Boron trigger kit.

The weird shit started with the buffer tube assembly. The tube they send has a little U notch cut into the threaded area of the buffer tube. I was always taught to run the buffer tube until it is flush with the internal receiver wall, and has more bite on the buffer retaining pin. So thats what I did, and the notch fits perfectly around the buffer pin. That did not end up working out. The rear of the carrier was hitting the tiny portion of the buffer tube that was just a hair past the receiver wall. It may it hard to close and open the upper onto the lower and felt off when you charged it.


So I took the castle nut back off and unscrewed the buffer tube one rotation and tried again. That worked and everything went together ok. However, the short buffer and backed off buffer tube, makes the buffer a little off balance and the carrier hits it when you close the upper onto the lower. I was worried backing it off might push the carrier closer to the receiver wall, but there is ~1/8" of space.



I got her all together and took out 4 mags of ammo. 2 mags were some remanufactured "M80", which I knew is sort of low power, and some Korean surplus that has some serious zip to it. Very good ammo, but feels/shoots on the high end of 7.62 ammo. Ran a little over a 100rds without a single hiccup. I can understand why PSA went to the AGB's, and I will say, it was probably a good idea they did, especially for the average owner of a PA10 who doesn't get into them like someone on here might. I set the AGB to what the card recommended. 17 "clicks" in from zero for .308 Winchester. Wayyyy over gassed. Even the reman'ed M80 was spitting hard at 2 o'clock, and the Korean surplus was at the 1 o'clock and erratically bouncing around.

I walked back to my shop (200yd range in my backyard), and adjusted the gas block 5 clicks toward zero. Ran half a mag of the M80 and it wouldn't cycle, but just barely. Went two clicks back open and was able to run both the M80 and the Korean hot surplus just fine. Both brands were a nice 3 oclock pattern in a smaller pile. Ran 3 rounds of PPU 168 BTHP that I had laying around and same thing, same pile.

I got the RT-6 field zero'ed and clanged some 66% IPSC steel at 100yds. Going to try and hit a range day at our club next week if its nice and try to do some of the accuracy testing. I've got some Federal Berger 168's, 175 SMK's, Fusion 150's, and M118. I'll most likely just go ahead and put the Armalite buffer system on now. Stock kit ran fine, but I'd like to see how the nicer setup effects it at all.

I had to cut my own U-notch into my Armalite tube in order to get it fully screwed in. I tried installing it, noticed the problem, and backed the tube out enough to remove the buffer retainer. Then screwed it back in where it needed to be, checking alignment with the end plate and tightened to castle nut hand tight. I marked exactly where the notch had to be and removed the tube. Used a 1/4" chain saw file to do the notch.


However, the short buffer and backed off buffer tube, makes the buffer a little off balance and the carrier hits it when you close the upper onto the lower.
So I guess I can add this problem to my list of "Short buffer drawbacks". I do remember this when I was running my short buffer but I just went with it and didn't have any problems with that. The Armalite buffer doesn't tilt downward as much as your picture from the side shows, at least not in mine.

I have marks in mine where the carrier hit at some time in it's past struggles but I didn't know it until a lot of changes had been made. It does not hit now for sure. If you have one that hits and you just can't figure out why, you can drop a quarter into the bottom of the buffer tube for a spacer.

My gun was a definite learning experience as I had problems with ALL of the woes discussed on the PA10 platform and then some. Much of it was also self-inflicted because I was going down too many rabbit holes at once. Defective brass on some of my reloads, headspace problems, loose adjustable gas block out of position, installed AR15 buffer spring once, on and on. Probably got 500 rds through it just trying to reach a reasonable level of reliability.

 

[Gustav7]

Looks normal to me. Might be a good candidate if you wanted to cut down the barrel and pin it.

I will be doing this. Although I'm pretty sure I'll just be cutting back to 16". A buddy runs a CNC so I have the option to get it done for a few beers. I wanted to keep it legal and have the option to switch muzzle devices easier. This does not have a dedicated suppressor and I have no idea what I'd use when I get a dedicated one, so I need it to be flexible currently. That being said, PSA for some dumb reason has the skinnier part of the barrel behind the gas block and the heavy part in front, so lopping off 2" of the thicker barrel at the end should really be noticeable weight distribution wise.

I had to cut my own U-notch into my Armalite tube in order to get it fully screwed in. I tried installing it, noticed the problem, and backed the tube out enough to remove the buffer retainer. Then screwed it back in where it needed to be, checking alignment with the end plate and tightened to castle nut hand tight. I marked exactly where the notch had to be and removed the tube. Used a 1/4" chain saw file to do the notch.

However, the short buffer and backed off buffer tube, makes the buffer a little off balance and the carrier hits it when you close the upper onto the lower.
So I guess I can add this problem to my list of "Short buffer drawbacks". I do remember this when I was running my short buffer but I just went with it and didn't have any problems with that. The Armalite buffer doesn't tilt downward as much as your picture from the side shows, at least not in mine.

*snip*...Probably got 500 rds through it just trying to reach a reasonable level of reliability.

Interesting on the U-notch you had to cut. I'll see how mine does when install it.

Ya I'm not sure if I just got lucky, or the Gen 3's are really that much better. I think the AGB is going to help the reputation a lot with the average shooters. Although I don't think its the perfect solution (obviously), it's going to make a better experience for a lot of shooters.

 

[308pirate]

Going to try and hit a range day at our club next week if its nice​

Let me know when, I might stop by if I can.

 

[Gustav7]

Let me know when, I might stop by if I can.

Will do, works slowing down, so I can finally take some days off. Eventually I'd like to take it out to TVP or Raynors, but the covered 100yd will work for now.

 

[bfoosh006]

It was always told to me that it was a cover up for not adhering to proper design. A lot of this info is form 308AR forum, as there are a few guys over there that specialize in large frame, now that being said, one of them reeeeally hates PSA and not because they're cheap. Supposedly a rep from PSA was on that forum and a few guys went out of their way to help them understand the simple fixes they needed to employ to get the rifles up to par, and they never listened. My BCG in this rifle has plenty of room in that area, even without the cuts, so I'm not worried.

I have no doubt that your buffer tube is running solid, although I'm positive your buffer and gas upgrades have helped. After inspecting and feeling the PSA buffer, I'm just not confident in it. I may be wrong, but I'm already set on using the Armalite one anyways. My main concern is no matter how you adjust the gas block, keeping the bolt locked up a little longer and not having such a violent unlock/extract phase is a positive in my eyes, especially when you get into suppressor use.

The carrier tilt got mentioned over on 308AR, but it was from a few years ago, so it may have been Gen1/Gen2 timeframe. As raggedy as the stock buffer system is, it ran well today. (see my new update)

PSA certainly went through a learning curve with their Large Frame version.
The lack of any kind of "Mil-Spec" guideline certainly didn't help anyone.
And I am sure it being "slightly" off at certain measurements helped avoid any "copying" issues.

Even to this day, there are a lot of subtle differences on a PSA large frame, enough that I don't recommend trying to use a PSA upper on any other brand Lower, even if the pins align up.
As for the supposed Rep. from PSA , ( which wasn't a Rep ) there is a lot, lot more to that story. And always 2 sides of any story.

The PSA OEM 2.5" buffer is less than inspiring, that is for sure. Adequate, is even border line of a decent description.
Kinda funny they had to label it "PA-10". ( Easier to install the correct one ?! )

Anyone here still running a OEM PSA 2.5" buffer ? Really curious how it has fared.

I will say the Tubbs and the KAK 5.3oz 2.5" buffer did help with cyclic speeds. I wish I had the forethought to switch back to the OEM setup, just to observe the differences.
At the time, the thought of the long life cycle of the Tubbs was a reason why I also use it. ( One less thing to remember to watch )
Frankly all my AR's use them, even my 9MM PCC uses a 308 Tubbs Flatwire. It Really calmed down that "Linda Blair" Excorcist blowback action, to a much more moderate Whinny the Pooh cycling.

Is this the Adj. GB you have ?
https://palmettostatearmory.com/psa-custom-750-diameter-click-adjustable-gas-block-7811021.html
Interesting description of it ... 5 clicks per 360 degree rotation , but a total of ( I can't remember what you said. )
Is there anything stopping you from backing it all the way out ?
And BTW, the PSA 2 Stage Nickel Boron Trigger is a Schmid Tool product, LOTS of manufactuers use / sell them under their name. Good triggers.

 

[308pirate]

Will do, works slowing down, so I can finally take some days off. Eventually I'd like to take it out to TVP or Raynors, but the covered 100yd will work for now.

Y U Not 300 yd qualified?

 

[msgriff]

Verifying that the carrier doesn't strike the receiver extension hub, like you did, is important, especially when using non-OEM parts. Another dimension to check is the distance between the bolt lugs and the bolt catch at full pull-back of the charging handle.

 

[BCP]

And BTW, the PSA 2 Stage Nickel Boron Trigger is a Schmid Tool product, LOTS of manufactuers use / sell them under their name. Good triggers.

I'll have to try one in my 716i, was gonna use a larue or g2s but they're either out of stock or too expensive right now.

 

[Gustav7]

Y U Not 300 yd qualified?

I am, just don't need it for this round. I was just going to shoot some different ammo for groups at 100 and see how the barrel shoots overall.

 

[Gustav7]

Even to this day, there are a lot of subtle differences on a PSA large frame, enough that I don't recommend trying to use a PSA upper on any other brand Lower, even if the pins align up.
As for the supposed Rep. from PSA , ( which wasn't a Rep ) there is a lot, lot more to that story. And always 2 sides of any story.

I would agree there, I mainly went the PSA/Aero route so that I could have the most amount of widely available parts that would normally cause issues. A spare LPK from PSA and a spare bolt/firing pin, etc.
LOL, ya it seems like I'm looking at some trash floating on the ocean with that story. I should probably just shut up about it.

Is this the Adj. GB you have ?
https://palmettostatearmory.com/psa-custom-750-diameter-click-adjustable-gas-block-7811021.html
Interesting description of it ... 5 clicks per 360 degree rotation , but a total of ( I can't remember what you said. )
Is there anything stopping you from backing it all the way out ?
And BTW, the PSA 2 Stage Nickel Boron Trigger is a Schmid Tool product, LOTS of manufactuers use / sell them under their name. Good triggers.
View attachment 8065578

Yes thats it. Ya I counted 27ish clicks. The paper said 26. I did not back it out, but did screw it in until it stopped, then went 16 clicks open. I ended up at 13ish clicks open. They say 5 position? Who knows.

My trigger is a single stage but its coated in something. Looks to be a hazy nickel boron type coating, as its definitely not phosphate or the standard black/gray. I just assumed nickel boron. Its smoother than most milspec, so it breaks a little cleaner. Still probably 5-6lbs though; I don't have a gauge.

 

[308pirate]

I am, just don't need it for this round. I was just going to shoot some different ammo for groups at 100 and see how the barrel shoots overall.

But we should smack some steel after you get your groups.

 

[bfoosh006]

I would agree there, I mainly went the PSA/Aero route so that I could have the most amount of widely available parts that would normally cause issues. A spare LPK from PSA and a spare bolt/firing pin, etc.
LOL, ya it seems like I'm looking at some trash floating on the ocean with that story. I should probably just shut up about it.


Yes thats it. Ya I counted 27ish clicks. The paper said 26. I did not back it out, but did screw it in until it stopped, then went 16 clicks open. I ended up at 13ish clicks open. They say 5 position? Who knows.

My trigger is a single stage but its coated in something. Looks to be a hazy nickel boron type coating, as its definitely not phosphate or the standard black/gray. I just assumed nickel boron. Its smoother than most milspec, so it breaks a little cleaner. Still probably 5-6lbs though; I don't have a gauge.

Do you have the means to measure the firing pin tip size ?

Adj. GB wise, as long as it works, Lol ... I would prefer the "26" clicks over just 5 though.

If the trigger has a "S" stamped on the hammer, it is probably Schmid Tool as well

It is a helluva story, but "Let Them be Them", Lol

 

[mtrmn]

How was the Nickel Boron PSA 2 stage?

I'm sorry I missed this question before.This trigger is everything I want in a trigger and is a vast improvement over any single stage I've ever used. IN MY OPINION. I have to stress that because I'm not looking for a benchrest quality trigger or anything like that. I like the 2-stage because I can have a 5 lb trigger that feels like a 2 lb trigger. (I just pulled those numbers out of my ass, I have no idea what it really is) For example, the first stage can be 3 lb takeup to a certain stopping point, then just add 2 more lbs to what I'm already holding for a very clean break.

 

[gopherslayer]

I hope they’ve improved the trigger because my 2 stage is just OK. It’s better than milspec but not by a lot.

 

[BCP]

I hope they’ve improved the trigger because my 2 stage is just OK. It’s better than milspec but not by a lot.

They're 69 bucks I doubt they feel like a Geissele that costs three times as much. My main concern with cheaper 2 stage triggers is failure. An RRA that turned spongey full automatic on me for example.

 

[Gustav7]

Do you have the means to measure the firing pin tip size ?

Adj. GB wise, as long as it works, Lol ... I would prefer the "26" clicks over just 5 though.

If the trigger has a "S" stamped on the hammer, it is probably Schmid Tool as well

It is a helluva story, but "Let Them be Them", Lol

I do, I can check it with my Starrett calipers. Appears to fit very nicely in the bolt head though.

I just get hesitant with the parts that see the most action (heat/pressure/repetitive motion/etc). PSA does charge $50 for the gas block, so its not dirt cheap, but $30-$50 away from the name brand competitors. Maybe it works forever, maybe it breaks, but generally I prefer to upgrade to something more reputable in that area. It DOES currently function as intended though.

LOL, probably a good call. I'm sure every forum has their dramas. You just can't escape it.

 

[Gustav7]

**Update**​

Got to the range today to do some accuracy testing and see how it show the 2nd 100rds of ammo. It was flawless through another 90 rounds using 7 different ammo selections from 147 to 175.

The way I did it was I started with the stock rifle and did a 5 shot group of every ammo, then changed the buffer tube/spring/buffer out to the armalite setup and shot a 2nd 5 shot group of every ammo.
Keep in mind, I don't have a ton of time behind a large frame gasser and I'm using a Burris RT-6. Wind was blowing 90* from 10-20mph, so it's possible some group variation was the wind gusts. I did watch some of frank's large frame gasser videos, so I just tried to keep it consistent, follow through, and get a good NPA.

The ammo shot for groups was:
1.) Korean M80 surplus
2.) American Marksman Reman'ed "M80"
3.) PPU 168gr (not shown, 2-3 moa)
4.) Federal Fusion 150gr
5.) Federal Match 168gr Berger
6.) Federal Match 175gr SMK
7.) M118 (also 175smk I believe)

One interesting note is both 175gr ammo would not fully cycle at the current gas setting. I had to open the gas block up 2 clicks to feed the 175's correctly.
The Federal 168 Berger "felt" like the heaviest recoiling ammo I shot. I did not get chrono data but hope to next time.

Korean M80 - Both groups were right around 2.5-2.75moa Reman. M80 - Basically the same as the Korean M80 (2-3moa)

Federal Fusion 150gr. -- Smallest group of the day at 0.8moa. But also biggest group at 1.6moa. May have been me on the first group​

Federal Match 168gr Berger -- I thought this may have been the best, but fell right into the "average".​

Federal Match 175gr Sierra Matchking -- I felt overall, the 175's performed the best. The first group was when I found out the gas setting was quite right. I shot two, adjusted the the gas, then shot 3. Probably my fault.​

M118 (LC04) -- Shot better than I thought, but then again I have no experience with M118. 2nd group, 5th shot was called flyer. That group was shaping up to be pretty good too.​

In the end, I thought it was pretty decent for what it is. With match ammo, it's easily a 1-1.5moa rifle. I think with a better shooter, some tuning or maybe handloads, it'd be a solid 1 moa shooter.

The buffer change mid session did result in a little better average group size, not that I would attribute it to that entirely. After a few groups, I felt more comfortable, but then again, the last groups start to wear on you. Recoil impulse change was noticeable. Recoil felt more drawn out, and not so snappy, which I figured would be the case. Ejection pattern direction was the same for each ammo type, however the distance travelled was less after the buffer change. Ejection went from about 10-15ft to around 7-10ft.

This reaffirms the idea that an AGB is not the ONLY thing to be adjusted to make a rifle shoot better/smoother. This seems to be especially true on large frame but applies to small frame as well.


**Side Notes -- This milspec PSA trigger is pretty nice...that is compared to other milspec triggers. Very surprised how well it did in a precision setting. I could easily say its only a little heavier and "worse" than the original Geissele SSA (4.5lbs)

The American Marksman M80 Reman'ed ammo is super cheap, comes bulk packaged, and is dirty ammo...as if it was never tumbled. However, it does come with LC brass and it performed just as well as the other surplus M80 I had did. So I'll probably buy more, and might try their M118 reman'ed. I did have one case blow a case head on me though, 3 shots into the day. Thought my magazine caught fire cause it was smoking so bad. First time for that ....

 

[mtrmn]

This reaffirms the idea that an AGB is not the ONLY thing to be adjusted to make a rifle shoot better/smoother. This seems to be especially true on large frame but applies to small frame as well.

I agree with this 100%. I don't even have a small frame with an adjustable gasblock.

 

[mtrmn]

The American Marksman M80 Reman'ed ammo is super cheap, comes bulk packaged, and is dirty ammo...as if it was never tumbled. However, it does come with LC brass and it performed just as well as the other surplus M80 I had did. So I'll probably buy more, and might try their M118 reman'ed. I did have one case blow a case head on me though, 3 shots into the day. Thought my magazine caught fire cause it was smoking so bad. First time for that ....
View attachment 8072448View attachment 8072450

THIS BRASS!!
That's NOT a case head separation. I had the same problem on a bunch of LCbrass from Top Brass I bought in the early 2000's. Those cracks are in the solid brass portion of the case head. It's a failure of the brass itself. I also experienced this during my journey to reliability with some of my reloads. It threw several major monkey wrenches into my troubleshooting process by giving me false indications of faulty reloading practices. Set me back months.
I bought the brass sometime before 2010 but didn't use any of it until 2015 or so while I was loading bulk ball ammo. I don't have any idea how much of this shit is still scattered amongst about 1500 rds I have already loaded.
I never contacted Top Brass because it had been several years since I bought it. I don't know if this is a fault of the LC brass or somehow damaged during processing, but I really don't see how processing once fired brass could do this without any other visible damage.
Cut the head off that case and you'll see big cracks in the head around the primer flash hole.

 

[mtrmn]

One of these blew my pmag out of the gun and stripped the groove in the plastic where the mag catch holds it.

 

[Gustav7]

I agree with this 100%. I don't even have a small frame with an adjustable gasblock.

With small frame I think most quality builds already have a decent buffer setup, so it’s already sort of “tuned”, and then they are an AGB and assume that’s what did 100% of the tuning.

When you start throwing in all variables and different chamberings or large frame, it becomes far more necessary. I suppose if I were to give advice to a new AR owner I’d suggest buffer tuning before AGB, whereas I used to think opposite.

 

[Gustav7]

THIS BRASS!!
That's NOT a case head separation. I had the same problem on a bunch of LCbrass from Top Brass I bought in the early 2000's. Those cracks are in the solid brass portion of the case head. It's a failure of the brass itself. I also experienced this during my journey to reliability with some of my reloads. It threw several major monkey wrenches into my troubleshooting process by giving me false indications of faulty reloading practices. Set me back months.
I bought the brass sometime before 2010 but didn't use any of it until 2015 or so while I was loading bulk ball ammo. I don't have any idea how much of this shit is still scattered amongst about 1500 rds I have already loaded.
I never contacted Top Brass because it had been several years since I bought it. I don't know if this is a fault of the LC brass or somehow damaged during processing, but I really don't see how processing once fired brass could do this without any other visible damage.
Cut the head off that case and you'll see big cracks in the head around the primer flash hole.

Oh damn. Thats not very reassuring considering its LC brass. I wonder if there was an issue with a batch of the components to make the brass or wrong combo of metals or something. Weird.

 

[mtrmn]

Oh damn. Thats not very reassuring considering its LC brass. I wonder if there was an issue with a batch of the components to make the brass or wrong combo of metals or something. Weird.

I kinda thought the brass may be too brittle etc. After I found this problem, I found out I could weed out most of it by inspecting the interior of the case with a light BEFORE loading it. There will be very visible cracks in the base. I used a mini maglite with a the curved fiber optic attachment. I think I weeded out around 75 rds of brass out of about 300 I had left. Trouble is, I loaded about 1500 rds of bulk 145 gr fmjs and put them up in ammo cans for future use. If you notice the headstamps they span multiple years, so I don't think this was limited to a small lot. I saw a few posts on other forums about the same problem and they all eventually arrived at the same conclusion that the brass was faulty after a long discussion mistaking it for case head separation.
To anyone reading this I want to make it clear that I am NOT blaming Top Brass for this. And the cracks are apparently present and visible before the "once-fired" brass gets reloaded.

 

[Gustav7]

I kinda thought the brass may be too brittle etc. After I found this problem, I found out I could weed out most of it by inspecting the interior of the case with a light BEFORE loading it. There will be very visible cracks in the base. I used a mini maglite with a the curved fiber optic attachment. I think I weeded out around 75 rds of brass out of about 300 I had left. Trouble is, I loaded about 1500 rds of bulk 145 gr fmjs and put them up in ammo cans for future use. If you notice the headstamps they span multiple years, so I don't think this was limited to a small lot. I saw a few posts on other forums about the same problem and they all eventually arrived at the same conclusion that the brass was faulty after a long discussion mistaking it for case head separation.
To anyone reading this I want to make it clear that I am NOT blaming Top Brass for this. And the cracks are apparently present and visible before the "once-fired" brass gets reloaded.

We'll see. I have another 100+ rds or so of it. It's so damn cheap and doesn't shoot bad, I'm tempted to chance it and buy more. Of course, this ammo was bought about 5-6 years ago, so hopefully the newer stuff would be good.

 

[BCP]

I have several hundred rounds of american marksman m80 and its all new LC 21 brass with crimped primers. Not reloaded. Accuracy is good enough for blasting rocks.

 

[12Bravo20]

I assembled a PSA Gen 1 PA10 lower and then purchased a complete 20" PA10 upper for it back in 2016. It is definitely over-gassed but I have not had any issues with the rifle. I have not spent the time yet to find the most accurate factory ammo for it yet. I have mostly just shot Winchester White Box ammo with it and get 1 1/2 MOA at 100 yards using a Primary Arms 4-14 HUD DMR scope.

My Savage Model 12 shoots the old Norma Tactical 150Gr FMJ extremely well so I thought I would try it in my PA10. That was a mistake and waste of good ammo. The PA10 did worse with the Norma Tac than it did with the Winchester White Box.

I need to try some of the Federal Gold Match 168Gr and 175Gr ammo in it along with seeing if I can tame the recoil down some. If none of that pans out, then I will look at changing it to a different caliber with less recoil.

 

[Gustav7]

I assembled a PSA Gen 1 PA10 lower and then purchased a complete 20" PA10 upper for it back in 2016. It is definitely over-gassed but I have not had any issues with the rifle. I have not spent the time yet to find the most accurate factory ammo for it yet. I have mostly just shot Winchester White Box ammo with it and get 1 1/2 MOA at 100 yards using a Primary Arms 4-14 HUD DMR scope.

My Savage Model 12 shoots the old Norma Tactical 150Gr FMJ extremely well so I thought I would try it in my PA10. That was a mistake and waste of good ammo. The PA10 did worse with the Norma Tac than it did with the Winchester White Box.

I need to try some of the Federal Gold Match 168Gr and 175Gr ammo in it along with seeing if I can tame the recoil down some. If none of that pans out, then I will look at changing it to a different caliber with less recoil.

Have you changed the Buffer? Spring? AGB?

 

[mtrmn]

I assembled a PSA Gen 1 PA10 lower and then purchased a complete 20" PA10 upper for it back in 2016. It is definitely over-gassed but I have not had any issues with the rifle. I have not spent the time yet to find the most accurate factory ammo for it yet. I have mostly just shot Winchester White Box ammo with it and get 1 1/2 MOA at 100 yards using a Primary Arms 4-14 HUD DMR scope.

My Savage Model 12 shoots the old Norma Tactical 150Gr FMJ extremely well so I thought I would try it in my PA10. That was a mistake and waste of good ammo. The PA10 did worse with the Norma Tac than it did with the Winchester White Box.

I need to try some of the Federal Gold Match 168Gr and 175Gr ammo in it along with seeing if I can tame the recoil down some. If none of that pans out, then I will look at changing it to a different caliber with less recoil.

To tame recoil, heavier buffer and spring.

I think the 20" rifle gas system works better with the standard substandard recoil system that PSA supplies in their kits. The ones we've had so much trouble with were mostly "midlength" 16" barrels, at least in my case.

 

[12Bravo20]

Have you changed the Buffer? Spring? AGB?

No I haven't done any of that yet. I really haven't shot the rifle in 2-3 years due to shoulder injuries along with having arthritis and fibromyalgia. I know that I need to at lease instal an adjustable gas block.

To tame recoil, heavier buffer and spring.

I think the 20" rifle gas system works better with the standard substandard recoil system that PSA supplies in their kits. The ones we've had so much trouble with were mostly "midlength" 16" barrels, at least in my case.

I am using a 308 rifle length buffer that came with the build kit from PSA.

Here is a photo of my PA10. Not in the photo is the MagPul PRS3 that is currently on the rifle.

I don't know if I want to spend a bunch of time and money on this to tame the recoil until I know how it shoots with premium ammo. As it is, the rifle has been 100% reliable for me.

 

[bfoosh006]

I agree with this 100%. I don't even have a small frame with an adjustable gasblock.

Lol, and IMHO don't waste your time on a 5.56. I tried one ( Adj GB ) on a 18" LtWt buffer / LtWt BCG / etc setup.. I couldn't feel any difference.

 

[bfoosh006]

To tame recoil, heavier buffer and spring.

I think the 20" rifle gas system works better with the standard substandard recoil system that PSA supplies in their kits. The ones we've had so much trouble with were mostly "midlength" 16" barrels, at least in my case.

16" ? Or 18" ?

I don't remember PSA selling 16" PA10 barrels. ( I could be wrong )

Gustav7 , I don't remember if you were able to measure the gas port size ?
I am curious if they have gotten smaller over the years. And the firing pin tip size ?

 

[Gustav7]

No I haven't done any of that yet. I really haven't shot the rifle in 2-3 years due to shoulder injuries along with having arthritis and fibromyalgia. I know that I need to at lease instal an adjustable gas block.

If you've got all that going on, I might not even mess around with large frame at all. If you do, I'd at least be dropping down to 6.5cm or something...but really I'd be looking at 6ARC in a small frame. No need to beat yourself up with all that going on.

If you stick with large frame... you're going to need to upgrade your buffer, spring, and most likely AGB regardless of caliber. If you drop down to 6.5cm or 6cm, you'll want a different carrier and bolt most likely, something like the Rubber City Armory or JP. You could always get a heavier 20-22" with a Rifle gas or Rifle +2. Some of those tuned guns like that have very little recoil compared to what you have now.

Gustav7 , I don't remember if you were able to measure the gas port size ?
I am curious if they have gotten smaller over the years. And the firing pin tip size ?

I did not measure firing pin tip yet, I can tonight if I remember.

Gas port was ~0.074-0.077"

 

[12Bravo20]

If you've got all that going on, I might not even mess around with large frame at all. If you do, I'd at least be dropping down to 6.5cm or something...but really I'd be looking at 6ARC in a small frame. No need to beat yourself up with all that going on.

If you stick with large frame... you're going to need to upgrade your buffer, spring, and most likely AGB regardless of caliber. If you drop down to 6.5cm or 6cm, you'll want a different carrier and bolt most likely, something like the Rubber City Armory or JP. You could always get a heavier 20-22" with a Rifle gas or Rifle +2. Some of those tuned guns like that have very little recoil compared to what you have now.



I did not measure firing pin tip yet, I can tonight if I remember.

Gas port was ~0.074-0.077"

I built a 6 ARC upper a few months ago just incase. It is a nice shooter. I was able to shoot 1" groups with Hornady 103 Gr ammo and 3/4" groups with Hornady 108Gr ammo at 100 yards. I am using an 18" Odin Works barrel. I haven't had a chance to shoot any farther than 100 yards with it.

I have been thinking about putting a 6CM barrel on the PA10 since I can use the same bullets for it as the 6 ARC. I'm still in the decision making mode on the PA10 right now.

 

[D̷e̷v̷i̷l̷D̷o̷c̷A̷Z̷]

I built a 6 ARC upper a few months ago just incase. It is a nice shooter. I was able to shoot 1" groups with Hornady 103 Gr ammo and 3/4" groups with Hornady 108Gr ammo at 100 yards. I am using an 18" Odin Works barrel. I haven't had a chance to shoot any farther than 100 yards with it.

I have been thinking about putting a 6CM barrel on the PA10 since I can use the same bullets for it as the 6 ARC. I'm still in the decision making mode on the PA10 right now.

Please make an AR10 6CM if you go down that route. I’m interested but unsure.

 

[mtrmn]

I am no expert, but in my experience the adj gas block has done nothing to cut down on recoil. It's all in the heavier reciprocating mass and the spring rate to make it work. If anything, cutting back the gas while still using the too-light buffer made the gun too finicky about ammo and less reliable. There was a very fine line adjustment wise between running reliably and short stroking. When the gun didn't cycle properly, felt recoil was greater.

The heavy buffer and spring changed all that. My 308 recoil now is similar to a 556. IMO, buffer and spring are the first step, then fine tune with the gas block, if needed. If I had a bum shoulder though, I'd just go with the small frame and be done. Regardless of the caliber on a large frame, you'll still likely have to go through all these experiments to get everything right.

Longer barrels and gas systems are out of my very limited range of knowledge though so YMMV.

16" ? Or 18" ?

I don't remember PSA selling 16" PA10 barrels. ( I could be wrong )

Gustav7 , I don't remember if you were able to measure the gas port size ?
I am curious if they have gotten smaller over the years. And the firing pin tip size ?

Definitely 16" stainless bbl which was a heavy profile. I replaced it with a Faxon 16" pencil bbl to cut down on some of the ridiculous weight.

 

[matthias]

Its all a balancing act. Adjustable gas block can help reduce bottoming out of the buffer and felt recoil. A heavier buffer can help from the other end. No free lunch with recoil. Jist making it feel different and more plesant.

 

[12Bravo20]

I really need to consider getting rid of my PA10 and also my Savage in 308 due to my physical limitations. I hate to get rid of the Savage though since it shoots so well.

To stay on topic. I can say that my Gen 1 PA10 with rifle length gas system and rifle length buffer does work without issues. I have no experience with the Gen 2 or 3 PA10s or barrels with shorter gas systems.

 

[mtrmn]

No I haven't done any of that yet. I really haven't shot the rifle in 2-3 years due to shoulder injuries along with having arthritis and fibromyalgia. I know that I need to at lease instal an adjustable gas block.



I am using a 308 rifle length buffer that came with the build kit from PSA.

Here is a photo of my PA10. Not in the photo is the MagPul PRS3 that is currently on the rifle.

View attachment 8074522


I don't know if I want to spend a bunch of time and money on this to tame the recoil until I know how it shoots with premium ammo. As it is, the rifle has been 100% reliable for me.

OK, now I realize your using a rifle length buffer instead of the collapsible carbine style. If you do need to reduce recoil without going to a loud brake, go to Heavybuffers.com and use the "contact" page to explain the situation and ask questions. He'll get right back with you most of the time. You'll need the specs on your system, gas system length, gas port size etc. He can fix you up.

 

[Gustav7]

Gustav7 , I don't remember if you were able to measure the gas port size ?
I am curious if they have gotten smaller over the years. And the firing pin tip size ?

Firing pin tip is 0.077” … oddly almost the same as the gas port lol

 

[bfoosh006]

I did not measure firing pin tip yet, I can tonight if I remember.

Gas port was ~0.074-0.077"

Mine are ( from my old thread, 2017 ) SS 18" Mid-Length .070 GP, and the Nitrated 18" is .066 GP , also Mid-Length
I will have to dig out the FP tip size, I thought I had that written down, but that wasn't it... the one I had written down was for a "experimental High Pressure FP" with a tapered shaft at the front.

Left hand one, .068 tip

 

[bfoosh006]

No I haven't done any of that yet. I really haven't shot the rifle in 2-3 years due to shoulder injuries along with having arthritis and fibromyalgia. I know that I need to at lease instal an adjustable gas block.



I am using a 308 rifle length buffer that came with the build kit from PSA.

Here is a photo of my PA10. Not in the photo is the MagPul PRS3 that is currently on the rifle.

View attachment 8074522


I don't know if I want to spend a bunch of time and money on this to tame the recoil until I know how it shoots with premium ammo. As it is, the rifle has been 100% reliable for me.

FWIW, KAK makes a 9.3oz rifle length buffer for the LFAR. I use those with the Tubbs 308 Flatwire in my rifle length setups.
More of a gentle cycle.

https://www.kakindustry.com/kak-308-rifle-buffer-heavy

 

[12Bravo20]

FWIW, KAK makes a 9.3oz rifle length buffer for the LFAR. I use those with the Tubbs 308 Flatwire in my rifle length setups.
More of a gentle cycle.

https://www.kakindustry.com/kak-308-rifle-buffer-heavy

Thank you for that link. That is something to look into. Though I wonder if changing the buffer weight by 4 ounces would cause any issues.

 

[mtrmn]

Thank you for that link. That is something to look into. Though I wonder if changing the buffer weight by 4 ounces would cause any issues.

If it acts overgassed now probably not. If it does, and it has the internal weights like most buffers, you can take it apart along with a standard buffer to mix/match the steel and tungsten weights to suit your gun. It should cut the recoil down to where it's a pleasure to shoot. I shoot my old A2 Bushmaster 308 sometimes just to feel the action work. I'm a mechanic and it sends a thrill up my leg to feel all that machinery work it's magic lol. It has a Heavybuffers.com buffer and spring combo.

 

[bfoosh006]

Thank you for that link. That is something to look into. Though I wonder if changing the buffer weight by 4 ounces would cause any issues.

FWIW... I have tried some very heavy reciprocating mass weights in my PSA PA10's and they still functioned at normal temps ( never tried them in zero degree temps with the high mass setup )
When I say heavy, that setup had a standard 308 BCG, a Tubbs CWS added ( 4.05oz slides into the tail of the BCG ) , the 9.3oz 308 rifle buffer, and a Tubbs 308 recoil spring.

My PSA's functioned as intended. I do routinely use the 9.3oz KAK buffer and the Tubbs 308 Flatwire on my rifle stocked PA10 / 65's.

The recoil impulse is a more "steady" push as opposed to a sharp kick with a lighter setup.
Even more so with an Adj. GB limiting the gas.


Anyway, if you want to try the 9.3oz out, and the Tubbs recoil spring send me an IM, I'll let you borrow one.

 

[12Bravo20]

@bfoosh006 I appreciate the information and the offer.

I definitely have some decision making to do, especially after looking at the cost and availability of different barrels. And I do need to shoot the rifle with better ammo to see how accurate it really is before putting more money into it.

 

[mtrmn]

Just out of curiosity I weighed the rifle length buffer in my Bushmaster BAR10 A2 rifle. It came from Heavybuffers with a spring and it weighs 9.3 oz. The rifle has a 20" bbl, non-removable carry handle and standard triangle tower gas block/front sight. For anyone who doesn't know, this rifle is the predecessor to the RRA LAR308 which uses FN FAL magazines. Aside from all that frivolous info, it operates pretty flawlessly with this buffer/spring combo, with/without the suppressor. It's easy to painlessly run a couple hundred rds through this gun and not even realize you shot that much until you pick up the brass. That is with a healthy shoulder of course.

 

[12Bravo20]

I weighed the rifle length 308 buffer I have from PSA and it weighs 5.4 ounces. All of my standard AR15 rifle buffers weigh either 5.0 or 5.1 ounces.