AR15 Cycling Issues

[mkrem]

....don't take this personally, but throughout this thread the common symptoms of weakened ejection pattern appears when using Wolf steel cased ammo, even when using "standard" recoil system components. The use of RazorCore & "HOT" handloads gives you a 3-4 o'clock ejection pattern & reliable functioning.

...if getting it to function reliably with the Wolf Steel cased ammo is a necessity, then you will have to "lighten" components in the recoil system, i.e., lighter buffer spring rate, lighter buffer weight, lighter BCG, either individually or in combination. It also means that when you switch to other brands of ammo, you may experience the reverse of under gassing.

Yes I agree the common denominator is shooting wolf.

But the rifle itself, by all accounts, should be able to function with wolf using standard components and pushing an ejection pattern of 3-4 o’clock. And it should certainly have a 1 o’clock or some aggressive ejection pattern with quality factory ammo and very hot reloads when the gas system is wide open imo. but then again I’m not an expert. My knowledge is just derived from experience and the all knowing internet lol

Maybe I am putting too much on ejection pattern, but a rifle that short strokes is unacceptable none the less.

 

[r.tenorio671]

Yes I agree the common denominator is shooting wolf.

But the rifle itself, by all accounts, should be able to function with wolf using standard components and pushing an ejection pattern of 3-4 o’clock. And it should certainly have a 1 o’clock or some aggressive ejection pattern with quality factory ammo and very hot reloads when the gas system is wide open imo. but then again I’m not an expert. My knowledge is just derived from experience and the all knowing internet lol

Maybe I am putting too much on ejection pattern, but a rifle that short strokes is unacceptable none the less.

...TBH, I'd shitcan the usage of that particular Wolf ammo.

If I was stuck with a large cache of it, then I'd build/configure a platform that had enough adjustability to use it and normal ammo as required. But I would always be conscious of that "unreliability" factor and hesitant to use it when it mattered.

 

[mkrem]

...TBH, I'd shitcan the usage of that particular Wolf ammo.

If I was stuck with a large cache of it, then I'd build/configure a platform that had enough adjustability to use it and normal ammo as required. But I would always be conscious of that "unreliability" factor and hesitant to use it when it mattered.

Lol I really don’t disagree with you at all. True statements. But until I get my Dillon up and running, the wolf stockpile is what it is, a Shtf stockpile.

Regardless, I’m hoping that BA opening up the gas port fixed all issues.

 

[r.tenorio671]

Lol I really don’t disagree with you at all. True statements. But until I get my Dillon up and running, the wolf stockpile is what it is, a Shtf stockpile.

Regardless, I’m hoping that BA opening up the gas port fixed all issues.

....it may fix the Wolf issue, but it may have introduced a new issue once you use other COTS ammo, i.e., over-gassing.

 

[Milf Dots]

I have tried the rifle soaking wet with oil, properly lubed, as well as dry. If drilling out the gas port didn't fix it, the last thing it could be is that the lower is out of spec. Unfortunately, I can't send it in because it is registered. So the mftr says.

I'd send the rifle to SOTAR so he can blueprint it and find the issue(s).

 

[Paradox]

I built a URG-I Block 3 "Clone" and am experiencing cycling issues. I have exhausted about all my knowledge and am now here seeking opinions and advise.

I am using: Aero M4E1 upper and lower, Gissele SSA-E , 14.5" Faxon Gunner (i think), full auto bolt carrier group, MK14 Handguard, midlength gas system w/ adjustable gas block, H2 Buffer. I don't have the rifle in front of me so I can't verify all the brands at this time.

Background: I attempted to get the rifle on paper with wolf ammo and it would not cycle at all. It is my understanding that wolf is lower pressure ammo so I did the same thing with commercial brass. This helped to reduce the cycling issues but the rifle was still unreliable and short stroking.

My attempted fix: I ensured the gas block was wide open, made sure the gas tube was clear of obstructions, verified the gas block was installed correctly, reduced the H2 buffer to H1, reduced the H1 buffer to carbine, verified bolt function and gas rings were okay, changed buffer springs, modified buffer springs to lessen bolt load. None of these "fixes" allowed me to achieve reliable cycling as it continues to short stroke and is throwing brass at the 5 o'clock position. My last thought is that the gas port needs drilled out, but I feel like faxon should know what they are doing and i should not have to modify such.

Any input would be greatly appreciated as this rifle is no more than a paper weight at this point!

 

[Paradox]

5 oclock is a gas problem, should be 3-430is tops

 

[newageroman]

Further disassembly looks to be gas block just a tad off center(but still in line with the port on the barrel), and a dirty gas tube. we will see if that fixes it. I will probably clean the bolt in the meantime.

Fixed! dirty gas tube. It runs again. I pinged the 380 yd plate about 10 rounds fast fire Sat.
learned a lot - thx for the tips.

Press (bullets) or cry like the rest...

 

[Milf Dots]

Fixed! dirty gas tube. It runs again. I pinged the 380 yd plate about 10 rounds fast fire Sat.
learned a lot - thx for the tips.

Press (bullets) or cry like the rest...

Dirty gas tube- what a thing to have to worry about. Imagine being in the middle of battle, say, in Wanat, and having that problem.

 

[TheOE800]

Dirty gas tube- what a thing to have to worry about. Imagine being in the middle of battle, say, in Wanat, and having that problem.

Symptom of a greater issue? Debris? Really dirty ammo? I’ve never cleaned a gas tube.

 

[Paradox]

I built a URG-I Block 3 "Clone" and am experiencing cycling issues. I have exhausted about all my knowledge and am now here seeking opinions and advise.

I am using: Aero M4E1 upper and lower, Gissele SSA-E , 14.5" Faxon Gunner (i think), full auto bolt carrier group, MK14 Handguard, midlength gas system w/ adjustable gas block, H2 Buffer. I don't have the rifle in front of me so I can't verify all the brands at this time.

Background: I attempted to get the rifle on paper with wolf ammo and it would not cycle at all. It is my understanding that wolf is lower pressure ammo so I did the same thing with commercial brass. This helped to reduce the cycling issues but the rifle was still unreliable and short stroking.

My attempted fix: I ensured the gas block was wide open, made sure the gas tube was clear of obstructions, verified the gas block was installed correctly, reduced the H2 buffer to H1, reduced the H1 buffer to carbine, verified bolt function and gas rings were okay, changed buffer springs, modified buffer springs to lessen bolt load. None of these "fixes" allowed me to achieve reliable cycling as it continues to short stroke and is throwing brass at the 5 o'clock position. My last thought is that the gas port needs drilled out, but I feel like faxon should know what they are doing and i should not have to modify such.

Any input would be greatly appreciated as this rifle is no more than a paper weight at this point!

Being its unquestionably under gassed, have you tried different gas block? or tube? and verified barrel port is clear. and have you tried any other ammo? If it was simply not cycling bolt far enough to pick up the next round, then i'd look at the bolt, buffers etc. I had an issue with a 308 and turned out to be some roughness on new bcg, so emery paper and boat load of oil solved issue. in your case the 5 oclock is the biggest tell its not gas is being limited in some way. swap out tube and block and see what happens, its an easy enough test.

 

[TonyTheTiger]

Symptom of a greater issue? Debris? Really dirty ammo? I’ve never cleaned a gas tube.

Me neither, I've had one gas tube outlive 3 barrels and it's still clean as can be inside.

 

[mkrem]

Being its unquestionably under gassed, have you tried different gas block? or tube? and verified barrel port is clear. and have you tried any other ammo? If it was simply not cycling bolt far enough to pick up the next round, then i'd look at the bolt, buffers etc. I had an issue with a 308 and turned out to be some roughness on new bcg, so emery paper and boat load of oil solved issue. in your case the 5 oclock is the biggest tell its not gas is being limited in some way. swap out tube and block and see what happens, its an easy enough test.

I have done all the above and nothing changed. BA opened the gas port in the barrel but i have not had a chance to see if that helped.

 

[Paradox]

I have done all the above and nothing changed. BA opened the gas port in the barrel but i have not had a chance to see if that helped.

Well with a 14.5" barrel the correct buffer should be the H at 3.8oz with 62gr M855s, Have you tried that combo? These would be std M4 specs from government specs. don't recall if you tried the 3oz mil-spec. What is the length of the buffer spring? carbines are 10.0625-11.25" here's a link it all the stuff everyone mentions but maybe something pops up. how old is bcg? been taken apart? any binding or rough marks on it? how many rounds through this gun? new and tight still? Its always something stupid, be curious what it ends up being. Good Luck

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[mkrem]

Well with a 14.5" barrel the correct buffer should be the H at 3.8oz with 62gr M855s, Have you tried that combo? These would be std M4 specs from government specs. don't recall if you tried the 3oz mil-spec. What is the length of the buffer spring? carbines are 10.0625-11.25" here's a link it all the stuff everyone mentions but maybe something pops up. how old is bcg? been taken apart? any binding or rough marks on it? how many rounds through this gun? new and tight still? Its always something stupid, be curious what it ends up being. Good Luck

Troubleshooting Your AR Build

Troubleshooting Your AR Build

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Yes, I’ve tried that buffer combo. The buffer spring is a carbine. Not sure on the length but I’ve tried two different ones. I’ve tried a few different bcgs and all the same deal. Gun is brand new, less than 200 rounds I’m sure.

I’m sure now that BA drilled the gas port another size it will function. We shall see.

Edit: good article. Thanks for sharing!

 

[Paradox]

Yes, I’ve tried that buffer combo. The buffer spring is a carbine. Not sure on the length but I’ve tried two different ones. I’ve tried a few different bcgs and all the same deal. Gun is brand new, less than 200 rounds I’m sure.

I’m sure now that BA drilled the gas port another size it will function. We shall see.

Edit: good article. Thanks for sharing!

Check bolt with a set of reader or magnifying glass, on new stuff like my 308 my drown in oil was like desert compared to another, i stripped bcg, emery cloth on rails ran inside upper amd soaked that whore in a bucket of oil overnight then drained for a few hours cleaned up real well oiled real well and when I say well I mean every part of that piece of shit so much so that it was running at the seams when to the range got 10 rounds out, then rapid fire that thing for 120 rounds back to back as fast S i could pull the trigger though went from 100 rounds back to back and now it will eat anything sometimes this new stuff just has tolerances that are too much and you have to beat them in if you can honestly rule out the gas system not much left and orderly mine was not drowning it in enough oil and removing some of the crude machining marks left on the bolt

 

[TonyTheTiger]

 

[r.tenorio671]

Dirty gas tube- what a thing to have to worry about. Imagine being in the middle of battle, say, in Wanat, and having that problem.

.....I'm wondering too about this gas tube clogging report. Not saying it's invalid, just trying to figure out how/what may be causing it considering the low round count involved.

..."moon dust" was a real thing in my AO, fortunately we had access to a "cleaning station" that pumped/circulated cleaning fluid (PERC?) throughout the disassembled receivers. I recall it had an attached "wand" that could be used to pump fluid thru those hard to reach areas. If the tip of the wand was pressed up against the end of the gas tube that inserted into the gas key, it would flush out the gas tube as well. I suspect the "station" was some kind of re-purposed parts cleaning & dunk tank/apparatus some KBR/MPRI/unit OMS person came up with. It was used "frequently" ...and greatly appreciated

 

[newageroman]

I did shoot a bunch of old W748 with it, The gas block was clocked just a tad but the gas port circle from the barrel was still inside the dircle from the gas block so. I soaked the gas tube in gasoline and tried a couple of pipe cleaners but it never did clean up and was cruddy after cleaning you could still blow air through it. I should have kept it straight for a comparitive test, but after I installed the new one I bent the old one up as to not use it again. What led me on to the gas tube is someone said they shot a bunch of LeverEvolution and it clogged their gas tube up. I've shot a bunch of LeverEvolution as well.

 

[2aBaC̶a̶]

sounds like a buffer/ spring issue. You might look into the JP scs with the spring kit or an Oden adjustable buffer. Ive ran into issues with steel case and heavier buffers.

 

[r.tenorio671]

I did shoot a bunch of old W748 with it, The gas block was clocked just a tad but the gas port circle from the barrel was still inside the dircle from the gas block so. I soaked the gas tube in gasoline and tried a couple of pipe cleaners but it never did clean up and was cruddy after cleaning you could still blow air through it. I should have kept it straight for a comparitive test, but after I installed the new one I bent the old one up as to not use it again. What led me on to the gas tube is someone said they shot a bunch of LeverEvolution and it clogged their gas tube up. I've shot a bunch of LeverEvolution as well.

...TBH, based on my use of the household cleaner "CLR" to clean my VG6 Gamma brake on my 6ARC build (both 748 & LVR loads), I could imagine using something like a ketchup bottle with a flexible hose on it to fill the gas tube from the receiver end. A foamie ear plug shoved down the barrel beneath the gas port could probably provide a seal so the CLR can do its work. After draining I'd follow it up with a 90% alcohol soak/flush.

...but, again I'm still trying to see LVR alone being the cause....guess I'll find out eventually as LVR is what I'll be using.

 

[Tiribulus]

Check the gas port, I have had 2 separate barrels from different manufacturers with the wrong gas port, I used a set of drill bits to check diameter. Super easy to re drill just go slow, use a good oil and a new bit, or send it back and have the manufacturer fix it.

I also have had 2 different barrels from 2 different companies recently with undersized gas ports. The digital calipers don't lie.

 

[Milf Dots]

I also have had 2 different barrels from 2 different companies recently with undersized gas ports. The digital calipers don't lie.

Pin gauges are the truth tools for gas ports.

 

[Tiribulus]

Pin gauges are the truth tools for gas ports.

Not that I'm disputing that, but most people don't have AR specific pin gauges Including me.

 

[Shoebox]

sounds like a buffer/ spring issue. You might look into the JP scs with the spring kit or an Oden adjustable buffer. Ive ran into issues with steel case and heavier buffers.

I'm having similar issues with my BA barrel, 18" Wylde with rifle gas system. I have tried virtually everything, including the Strike adjustable buffer and Tubb flat spring, stock length and with 3 coils removed. The only thing left is gas port size. It measures 0.093" and I'm convinced that's too small for 18" with rifle gas length.

 

[2aBaC̶a̶]

I'm having similar issues with my BA barrel, 18" Wylde with rifle gas system. I have tried virtually everything, including the Strike adjustable buffer and Tubb flat spring, stock length and with 3 coils removed. The only thing left is gas port size. It measures 0.093" and I'm convinced that's too small for 18" with rifle gas length.

Honestly ive lost track of who has what problems in this thread.

The only rifle that ever gave me real problems tuning was my 18" 6.5CM. ended up with JP Low mass carrier, JP scs lightest configuration and agb open around half way. its still picky on mags but the Pmags work the best.

 

[Shoebox]

Honestly ive lost track of who has what problems in this thread.

I was just commenting that a different (lighter) spring and adjustable buffer are not always the solution. It appears that BA undersized some of their gas ports.

 

[Tiribulus]

It is becoming clear that for whatever reason, there are a lot of AR barrels floating around lately with undersized gas ports. I'm seeing it on forums and Reddit a few times a week at least.

I took my latest out yesterday after drilling this one out from .069 to .085 (PSA 10.5/Carbine) and for the second barrel in a row from different manufacturers, the undergassing issue is fixed. A couple dozen singles with 3 different types of ammo and it locks back solid every time without excessive recoil.

The first was a BA 16/Carbine that came with a port size of .053. Way too small for that barrel. I drilled it out to .065 and it runs like a champ.

 

[AMGtuned]

Not that I'm disputing that, but most people don't have AR specific pin gauges Including me.

Drill bits are available almost everywhere. Do a little math'n, then flip that sumbitch over, and slide the shank in the hole.


Edited to correct typo

 

[2aBaC̶a̶]

I was just commenting that a different (lighter) spring and adjustable buffer are not always the solution. It appears that BA undersized some of their gas ports.

never really considered port size as a variable. crazy to think that a high volume barrel manufacturer would get something like that wrong. but then again who knows how much testing actually went into determining gas port size. is it possible when some people open a gas port they are compensating for some other defeciency in the system creating a situation where an overgassed rifle functions. its almost like opening the gas port is the new Hot Fix.

 

[Shoebox]

never really considered port size as a variable. crazy to think that a high volume barrel manufacturer would get something like that wrong. but then again who knows how much testing actually went into determining gas port size. is it possible when some people open a gas port they compensating for some other defeciency in the system creating a situation where an overgassed rifle functions. its almost like opening the gas port is the new Hot Fix.

I have tried changing literally everything else, and nothing has completely solved the problem. Some ammo runs properly, some doesn't (all of which ran fine on the original PSA 16" carbine length barrel). The gas port size is about the only variable left.

When you buy a longer barrel, it and the gas tube (and possibly the block) are the only components changed. Should it be expected to run properly with everything else being milspec?

 

[TheOE800]

Undersized ports is a good trend.

 

[2aBaC̶a̶]

Undersized ports is a good trend.

how do you figure? or are you being facetious?

 

[Tiribulus]

how do you figure? or are you being facetious?

I think he's saying that undersized is better than oversized and overgassed. Which was the trend for quite a while.

 

[TonyTheTiger]

how do you figure? or are you being facetious?

It gives you a chance to tune a barrel to perfection with your ammo and forego an adjustable gas block. I like me an undersized port.

 

[Milf Dots]

At least two of the five articles I just read on AR troubleshooting claim one of the most common problems is OVERsized gas ports on barrels, and that some manufacturers do it so guns will run, with the claim that undersized ports won't allow rifles to cycle but oversized ports will. Pin gauges are the way to measure, or perhaps using a caliper or micrometer to measure new drill bits will result in a makeshift pin gauge.

Troubleshooting Your AR Build

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AR-15 Gas System Issues – School of the American Rifle –

AR-15 gas system issues such as under-gassed or over-gassed are common. To learn more, we spoke with Chad Albrecht at School of the American Rifle.

www.arbuildjunkie.com

How to Fix AR15 Malfunctions

How to Fix an Over Gassed AR-15

Most AR-15s are excellent firearms right off the factory line, but they sometimes need some fine-tuning to work their best. The good news is, you can solve many common issues with simple troubleshooting and adjustments, and by upgrading your components. If your rifle is performing under...

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AR-15 Failure To Feed | Expert Information | Wing Tactical

At one time or another, you will likely encounter a situation where your AR-15 has a failure to feed. Learn how to fix this with the help of Wing Tactical.

www.wingtactical.com

 

[Tiribulus]

Drill buts are available almost everywhere. Do a little math'n, then flip that sumbitch over, and slide the shank in the hole.

That's true, but already having digital calipers, I just use that.

 

[Tiribulus]

At least two of the four articles I just read on AR troubleshooting claim one of the most common problems is OVERsized gas ports on barrels, and that some manufacturers do it so guns will run, with the claim that undersized ports won't allow rifles to cycle but oversized ports will.

Right. That's the point. This seems to have changed recently to a noticable degree if you look around the web.

 

[Tiribulus]

It gives you a chance to tune a barrel to perfection with your ammo and forego an adjustable gas block. I like me an undersized port.

Meaning, you can open it up to whatever is perfect for your particular needs?

 

[Tiribulus]

I have tried changing literally everything else,

Find out what the size of the port is on your barrel. Not what the site says. What yours is. I bet it's too small. Which is a fairly trivial matter to correct actually. I did both mine on my lap without even taking the barrel out of the receiver. A few simple precautions and steps. Took maybe 15 minutes. They both shoot great.

 

[TheOE800]

It gives you a chance to tune a barrel to perfection with your ammo and forego an adjustable gas block. I like me an undersized port.

Bingo. If your average AR owner and American had just a wee bit mechanical inclination and the right tools, no problems.

 

[TonyTheTiger]

Meaning, you can open it up to whatever is perfect for your particular needs?

Correct.

 

[2aBaC̶a̶]

which is fine if you only ever shoot one specific ammo for the life of the rifle.

 

[r.tenorio671]

...not "trolling", but IMHO folks starting their builds with a variety of "non-standard" parts is what contributes to many of the reported issues. My personal view is start the build with "MIL standard" parts as a baseline and get thru the "break-in" period before starting to replace parts with the "latest & greatest", "Gucci-bling-bling", "I'm not a 'poor'" components. Doing this allows one to determine what specifically is deficient so the appropriate replacement part can be used to mitigate the deficiency and improve the reliability of the platform. The cost of "MIL standard" parts is minimal considering the pricing on some of the "enhanced" parts available and once replaced can be kept in one's parts bin for any future builds. I'm not talking about the "aesthetics" oriented parts, but those that affect the operation of the platform.

...Nomex suit donned, have at it...

 

[r.tenorio671]

....alot of bashing of the BA barrel's in this thread, and similar in many other threads. Deserved or not?...good question....

.... a common aspect to the bashing is that the posters were doing their own builds. I personally have not seen a corresponding amount of negative posts for those folks that have purchased a complete Aero rifle, in all calibers offered, in this forum or others I peruse. Aero's rifles use barrels that are produced by it's subsidiary, BA. If Aero is producing "reliable" rifles for COTS consumer purchase it does make one wonder about all of the bashing that occurs....

 

[Tiribulus]

....alot of bashing of the BA barrel's in this thread, and similar in many other threads. Deserved or not?...good question....

.... a common aspect to the bashing is that the posters were doing their own builds. I personally have not seen a corresponding amount of negative posts for those folks that have purchased a complete Aero rifle, in all calibers offered, in this forum or others I peruse. Aero's rifles use barrels that are produced by it's subsidiary, BA. If Aero is producing "reliable" rifles for COTS consumer purchase it does make one wonder about all of the bashing that occurs....

Friend, I measured the port on my BA barrel with a set of known accurate digital calipers. It measured 053. Which is drastically too small for a 16 inch carbine length barrel. I drilled it out with a 065 carbide drill bit, which instantly fixed my undergassing issue after trying everything else.

I'm not trying to be difficult for the sake of it, but I promise you my gas Port was too small.

I certainly don't know everything, but I am 58 years old and have been working on stuff my entire adult life, including firearms.

 

[r.tenorio671]

Friend, I measured the port on my BA barrel with a set of known accurate digital calipers. It measured 053. Which is drastically too small for a 16 inch carbine length barrel. I drilled it out with a 065 carbide drill bit, which instantly fixed my undergassing issue after trying everything else.

I'm not trying to be difficult for the sake of it, but I promise you my gas Port was too small.

I certainly don't know everything, but I am 58 years old and have been working on stuff my entire adult life, including firearms.

...not disputing YOUR experiences with BA barrel and if it worked for you, glad you found a workable solution.

...MY experiences with multiple BA barrels in multiple calibers in lengths from 7.5" thru 20" differed. I've yet to have an under-gassed tube from them in the past 10 years I've been using them. When paired with "MILSPEC" components, if anything they were all slightly "over-gassed" as common with many tubes offered up as individual components. MY only deviation from using "standard" parts is using SLR Adjustable gas blocks on MY builds (usually at 4-6 clicks open) for commercial/MIL ammo for reliable cycling & last round bolt hold open with a 3:30-4 o'clock ejection pattern.

..I've a decade+ on you and I'm still learning, thankfully!

 

[Tiribulus]

...not disputing YOUR experiences with BA barrel and if it worked for you, glad you found a workable solution.

...MY experiences with multiple BA barrels in multiple calibers in lengths from 7.5" thru 20" differed. I've yet to have an under-gassed tube from them in the past 10 years I've been using them. When paired with "MILSPEC" components, if anything they were all slightly "over-gassed" as common with many tubes offered up as individual components. MY only deviation from using "standard" parts is using SLR Adjustable gas blocks on MY builds (usually at 4-6 clicks open) for commercial/MIL ammo for reliable cycling & last round bolt hold open with a 3:30-4 o'clock ejection pattern.

..I've a decade+ on you and I'm still learning, thankfully!

To be clear, I'm not beating up on BA barrels at all. It's a fine barrel and shoots great. I'd buy another one. It's just that the port was too small. Once I got it squared away I was popping tomatoes at 200 yards despite my dimming eyesight lol.

I have actually seen recently a couple Aero rifles in the Aero subreddit that were bought as assembled uppers that weren't locking back on the last round. I bet their ports were too small too. Or some of them anyway. To me it's no big deal. Drill it out a bit and it's good to go

A couple weeks ago I grabbed a PSA AR pistol and IT was too small as well. Not just because it wouldn't lock back reliably, but because my digital calipers were telling me that the port was .053. Too small for a 10.5 in. carbine length barrel. I drilled it out to .085 and it's 100% and shoots great too.

I understand what you're saying. Drilling your gas port shouldn't be the first troubleshooting step and some guys just don't know what they're doing yet too.

However, I wouldn't lie to ya I am seeing this with increasing frequency the last several months and not just with home built weapons. Even so, home built or not isn't going to change the port size.

I bet we hear back from a couple of the guys in this thread eventually that opening up the port a hair fixed their problem. One guy on arfcom suggested that maybe the companies are trying to accommodate the increased use of suppressors, but that's another topic lol.

Anyway, no disrespect. I'm just saying how I see things.

 

[Shoebox]

Find out what the size of the port is on your barrel. Not what the site says. What yours is. I bet it's too small. Which is a fairly trivial matter to correct actually. I did both mine on my lap without even taking the barrel out of the receiver. A few simple precautions and steps. Took maybe 15 minutes. They both shoot great.

I did measure my port, it's 0.093".

...not "trolling", but IMHO folks starting their builds with a variety of "non-standard" parts is what contributes to many of the reported issues. My personal view is start the build with "MIL standard" parts as a baseline and get thru the "break-in" period before starting to replace parts with the "latest & greatest", "Gucci-bling-bling", "I'm not a 'poor'" components. Doing this allows one to determine what specifically is deficient so the appropriate replacement part can be used to mitigate the deficiency and improve the reliability of the platform. The cost of "MIL standard" parts is minimal considering the pricing on some of the "enhanced" parts available and once replaced can be kept in one's parts bin for any future builds. I'm not talking about the "aesthetics" oriented parts, but those that affect the operation of the platform.

Mine started as a normally functioning PSA 16" milspec rifle. The only change being the BA barrel, gas block, and tube. Nothing particularly fancy. The only variable truly was the barrel, and it stopped running reliably no matter what parts I threw at it. The only thing left is the gas port.

 

[TheOE800]

I did measure my port, it's 0.093".

Sorry what barrel is this we’re talking about? That’s a YUGE gas port; actually mil-spec for a 20” rifle length port is thereabouts.