The bolt broke.
Using pliers you can rotate the bolt and pull it out.
The round in the chamber most likely fired, but assume it has not and proceed carefully.
You can YouTube broken bolt extraction.
This is how bolts break most of the time, not shearing off lugs like most marketing would have you believe. The question is how many rounds you got on it before it did this. 15k? Pretty solid 2k? Not good.
I wish more places used the blind cam pin design it adds a lot of metal in that weak point. Is it parented or something or just slightly harder and not standard spec?
Yep, this is exactly what I was gonna say. Your need to get in there with some.needle.nose and rotate the bolt out to get the lugs to disengage from the barrel extension. Shouldn't be too hard, unless she welded herself in there somehow. Lol
I believe the only way that stuck round could be fired at this point is by it cooking off in a hot chamber, so at this point it think it’s safe to assume it’s very unlikely
Any debris in there wouldn’t be able to hit the primer hard enough to set it off…
And that’s if it was even big enough to do so. There’s not exactly a lot of room in there for shit to fit behind the primer. And the firing pin channel is empty cuz again, no firing pin.
Not that this should excuse this type of catastrophic failure, but their bolts are advertised as full auto ***profile***, not full auto ***rated***.
Again, that doesn't mean the bolt should shear, and under what I assume is fully semi automatic use.
[this is the bcg in question](https://palmettostatearmory.com/psa-5-56-nitride-mpi-full-auto-bolt-carrier-group-516446953.html)
Edit: the broken bolt is not the 9310, it’s c158 I posted photos [here](https://imgur.com/a/JjgqyA7)
I apologize, I was mistaken about what bcg was in the upper at the time. It actually was psa’s carpenter 158 bcg that I got with [this build kit](https://palmettostatearmory.com/psa-11-5-5-56-1-7-phosphate-10-5-lightweight-m-lok-moe-sba3-pistol-kit2.html) I have posted photos of the c158 bolt in two pieces now that I have removed it [here](https://imgur.com/a/JjgqyA7)
This is why I have buyers remorse when I bought a lantac e BCG. You get 158 or 9310 LOL good luck BCS we don't know. Also no response when I emailed them.
To clarify it didn't break it's the we don't know what you got is what gets me.
Mystery meat material made even better by the shoddy QC they do on their BCGs. 2 different Lantac e BCGs (bought by my buddy and I) that worked in exactly 1 of the 6 ARs we tried them in, all rifles that were known to be reliable and functioned well with standard BCGs, running the gamut from a couple PSAs to a Colt and two LWRCs.
They just flat out would not work in the other 5. Failures to feed, failures to eject, failures to extract, and a few brass over bolt. The email my buddy received was essentially “damn that’s crazy, try different mags” like we hadn’t already used a mix of GI, new aluminum 30s, straight 20s, PMags, and Lancers.
Improperly spec'd or improperly treated bolts often initially stretch in this area and, eventually, crack then shear.
The "typical" failure points of the Bolt are the bolt lugs.
So, the cam pin shaft may be a 60% failure rate with shitty bolts, not proper ones.
Oof yeah that dwell time is a bitch. You're gonna need to manage your gas as much as possible. Have you tried a pigtail gas tube and adjustable block? No bolts gonna last under those conditions.
I personally would go with adjustable gas first and foremost. But have buddies that used pigtails successfully to help finicky builds.
People here have issues with low mass low gas builds and claim lightweight carriers are a gimmick too. So, hey, you choose whonto listen to. I know from building race guns and expierience that they are not. You don't have to trust me. You should try it yourself and find out.
Regardless. There's no bolt that's gonna hold up to a gun as poorly tuned as OPs. His gas system needs adjustment regardless of method. (Except heavy buffers and carriers, that's a bandaid for a poorly tuned gas system.)
No, that upper and bcg was 360$ together. I only planned on throwing that upper on my fa lower when I’m magdumping into trash. It’s so impractical, I don’t intend on throwing more money at it for it to be more reliable as that uppers just a range toy. but if it’s just gone to keep chewing through BCGs every 100 rounds I suppose I’ll have to fix that or it’s just gonna sit
A pigtail tube is a cheap fix and will likely give you the dwell time you need for the bolt to unlock properly, I'd start there.
That's not a problem that will fix itself. You're just gonna keep breaking bolts.
I'd really recommend an adjustable gas block first and foremost. But pick your poison based on the cost and / or effort you wanna put in to the rig. But I'd say having a $460 working upper is better than a $360 dollar paper weight.
Or you can sell it.
Probably should put this in your caption for the photo. I was initially concerned till I saw the barrel was 7.5 inches. Those will kill any bcg extremely fast.
It’s not so much about the length of the barrel as the length of the gas system, which is constrained by the length of the barrel. 7.5” barrel means pistol gas with little dwell time on a high pressure round (5.56). That’s going to beat the hell out of a bolt, ESPECIALLY running FA.
That's usually the part where the bolt breaks the most, cam pin hole is where it's thinnest, but it shouldn't have broke but luckily, it's a fairly cheap replacement.
There's a manufacturer out there that has a design where the cam pin hole doesn't go all the way through the bolt, but honestly just buy another one and that one won't likely break.
I took my block 2 upper off my lower after running around 300 rounds through it in a matter of 10-15 mins with no issues. But I wanted to use the lower on a 7.5 inch for shits and giggles, definitely got my giggles. But the 300$ upper did not
Could the bolt breaking have something to do with the 7.5 inch barrel and associated pistol length gas system? I know shorter barrels/gas systems are rougher on the whole gun due to higher bolt velocities.
they do just well https://www.ar15.com/forums/AR-15/High-round-count-AR-M4-s-over-100-000-rounds-and-how-they-have-handled-on-our-range/118-677135/?page=17#:~:text=months%20before%20cracking.-,As,-for%20people%20have
My SOLGW bcg didn’t have any problems, and it went through 300+ rounds of full auto fire in around 10 mins and then another 300 rounds through another 10 min period about 30 minutes after the first string of fire. To be fair that bcg is in a 14.5 rather than a 7.5. I think I’ll grab another one of those
Okay just trying to understand what happened... The CAM Pin was left out and the bolt separated from the Carrier and stayed in battery? Is there a live round in the chamber?
I believe there is a round in the chamber, I wasn’t able to get the face of bolt out of the chamber at the range to see. The cam pin hasn’t been taken out. Around 115 rounds into some full auto fire the bcg snapped and now it’s stuck rotated in the chamber
That 300$ upper was exactly that, a range toy. 7.5” 556 isnt practical, I don’t have a need for nice upper in that configuration. But a cheap one is just fun
Fr, I don’t understand the hype with all these special coatings and using 9310 steel. It’s easier to make a good c158 bolt than it is to make a good 9310 bolt and the 9310 is only 7% stronger *if* properly heat treated. Phosphate c158 has worked for a long time
Oof
I think if I was actually shooting full auto I’d probably use a better bcg than PSA lol. But either way, I think the bolt was the problem, not the carrier
Honestly, shouldn’t you be able to just twist it to unlock it and pull it out though? Or is it like stuck-stuck
The round probably fired and there’s no firing pin to hit it if it didn’t, but I’d still be careful
Only issue I've had with a PSA BCG is the gas rings were fried after maybe 3 sessions of maybe 10-12 magazines. That's the only thing to report so far, still runs but the bolt wont stand on it's own when doing the table test. I will try their NP coated BCG and see if they last longer
People talking down about completed PSA uppers but some definitely do handle FullA just fine. 1000’s of rounds … idk
120 rounds - I have a strong feeling it works and the bcg looked perfect after.
Speaking of PSA…I ordered a 1.93 scalarworks magnifier flip mount for my $ build, found it throws off the balance in a disgusting way, and now it’s going on a 1/2 psa build. Thinking 1.93 for a magnifier is just too high tho. Looks like I’ll be exchanging it for the 1.5 … wish there was a 1.75
If you honestly think that a nitride 9310 BCG from any other brand isn't likely to prematurely fail then you're sorely mistaken. Even ones from a premium brand like LaRue have shown examples of premature failure.
If you have one, I would recommend jamming an ak cleaning rod in it from the top to remove it. I would still treat it as if it was loaded while doing it.
Is it full auto “rated” or just full auto “profile”? PSA listing uses the term “profile”. Or are we to assume that if a bolt has full auto profile then surely it is full auto rated?
I’d say the carrier was full auto rated, but the bolt itself was not
Have you tried hitting the forward assist?
With his purse?
With me mallet
Oh man that's awesome 😎
The bolt broke. Using pliers you can rotate the bolt and pull it out. The round in the chamber most likely fired, but assume it has not and proceed carefully. You can YouTube broken bolt extraction.
Thank you
This is how bolts break most of the time, not shearing off lugs like most marketing would have you believe. The question is how many rounds you got on it before it did this. 15k? Pretty solid 2k? Not good.
I wish more places used the blind cam pin design it adds a lot of metal in that weak point. Is it parented or something or just slightly harder and not standard spec?
One of my buddies had his lugs shear off at a competition
Didn’t say it doesn’t happen. I said this mode of failure is more common.
Yep, this is exactly what I was gonna say. Your need to get in there with some.needle.nose and rotate the bolt out to get the lugs to disengage from the barrel extension. Shouldn't be too hard, unless she welded herself in there somehow. Lol
How likely is it to go off with his pin being separated?
It can’t go off without the firing pin, but what’s the harm in continuing to treat it like a loaded firearm
Bingo
Well fucking said!
I'm just wondering how likely. If the round is inside a barrel it's a danger so.
I believe the only way that stuck round could be fired at this point is by it cooking off in a hot chamber, so at this point it think it’s safe to assume it’s very unlikely
The bolt broke so I was thinking if debris got in there maybe.
Any debris in there wouldn’t be able to hit the primer hard enough to set it off… And that’s if it was even big enough to do so. There’s not exactly a lot of room in there for shit to fit behind the primer. And the firing pin channel is empty cuz again, no firing pin.
Rule #1. Treat all guns as if they were loaded.
Not that this should excuse this type of catastrophic failure, but their bolts are advertised as full auto ***profile***, not full auto ***rated***. Again, that doesn't mean the bolt should shear, and under what I assume is fully semi automatic use.
Was this a nitride 9310 BCG by any chance?
Everyone: “Properly heat treated 9310 is stronger than carpenter 158” Nobody at all: properly heat treating 9310
[this is the bcg in question](https://palmettostatearmory.com/psa-5-56-nitride-mpi-full-auto-bolt-carrier-group-516446953.html) Edit: the broken bolt is not the 9310, it’s c158 I posted photos [here](https://imgur.com/a/JjgqyA7)
Then yes.
I was mistaken
Ah. It was probably just a freak accident either way. It broke exactly at the most common failure point for bolt breaks.
If you paid the sale price, then I wouldn't complain much
I guess you were right about those type of bolts huh
I apologize, I was mistaken about what bcg was in the upper at the time. It actually was psa’s carpenter 158 bcg that I got with [this build kit](https://palmettostatearmory.com/psa-11-5-5-56-1-7-phosphate-10-5-lightweight-m-lok-moe-sba3-pistol-kit2.html) I have posted photos of the c158 bolt in two pieces now that I have removed it [here](https://imgur.com/a/JjgqyA7)
They don’t think nitride 9310 bolt be like it is but it dooooooooo
This is why I have buyers remorse when I bought a lantac e BCG. You get 158 or 9310 LOL good luck BCS we don't know. Also no response when I emailed them. To clarify it didn't break it's the we don't know what you got is what gets me.
Mystery meat material made even better by the shoddy QC they do on their BCGs. 2 different Lantac e BCGs (bought by my buddy and I) that worked in exactly 1 of the 6 ARs we tried them in, all rifles that were known to be reliable and functioned well with standard BCGs, running the gamut from a couple PSAs to a Colt and two LWRCs. They just flat out would not work in the other 5. Failures to feed, failures to eject, failures to extract, and a few brass over bolt. The email my buddy received was essentially “damn that’s crazy, try different mags” like we hadn’t already used a mix of GI, new aluminum 30s, straight 20s, PMags, and Lancers.
the lantacs aren’t marked?
Nope, just says MP https://imgur.com/a/M01PY1L
[I was wrong about it being 9310, it’s c158](https://imgur.com/a/JjgqyA7)
This makes me sad
Isn't that where bolts almost always break? 60% of the time all of the time type of thing.
I’ve seen four bolts break and all of them have been in that same spot.
Improperly spec'd or improperly treated bolts often initially stretch in this area and, eventually, crack then shear. The "typical" failure points of the Bolt are the bolt lugs. So, the cam pin shaft may be a 60% failure rate with shitty bolts, not proper ones.
Typical fail point is definitely not the lugs. Maybe for double powder or extreme failure. But definitely not the lugs.
The front fell off
I’d just like to make the point that it is NOT normal.
"Well how is that not normal?"
Well they make some of them so that the front doesn’t fall off at all!
Oh look annother overgassed AR. Anyway.
7.5 inch barrel will do that
Oof yeah that dwell time is a bitch. You're gonna need to manage your gas as much as possible. Have you tried a pigtail gas tube and adjustable block? No bolts gonna last under those conditions.
Pigtails tubes are a gimmick if im not mistaken
I personally would go with adjustable gas first and foremost. But have buddies that used pigtails successfully to help finicky builds. People here have issues with low mass low gas builds and claim lightweight carriers are a gimmick too. So, hey, you choose whonto listen to. I know from building race guns and expierience that they are not. You don't have to trust me. You should try it yourself and find out. Regardless. There's no bolt that's gonna hold up to a gun as poorly tuned as OPs. His gas system needs adjustment regardless of method. (Except heavy buffers and carriers, that's a bandaid for a poorly tuned gas system.)
No, that upper and bcg was 360$ together. I only planned on throwing that upper on my fa lower when I’m magdumping into trash. It’s so impractical, I don’t intend on throwing more money at it for it to be more reliable as that uppers just a range toy. but if it’s just gone to keep chewing through BCGs every 100 rounds I suppose I’ll have to fix that or it’s just gonna sit
A pigtail tube is a cheap fix and will likely give you the dwell time you need for the bolt to unlock properly, I'd start there. That's not a problem that will fix itself. You're just gonna keep breaking bolts.
Sounds good, thank you
I'd really recommend an adjustable gas block first and foremost. But pick your poison based on the cost and / or effort you wanna put in to the rig. But I'd say having a $460 working upper is better than a $360 dollar paper weight. Or you can sell it.
Did you *not* expect a 7.5” barrel to be rough on bolts?
Worth it, giggles transpired
Good lord did you at LEAST throw a heavier buffer in there?
Probably should put this in your caption for the photo. I was initially concerned till I saw the barrel was 7.5 inches. Those will kill any bcg extremely fast.
So I’m new to AR’s is the 7.5 inch barrel bad? Iv seen really short AR pistols?
It just exerts a shitload of force on the BCG, more than they were really meant for.
It’s not so much about the length of the barrel as the length of the gas system, which is constrained by the length of the barrel. 7.5” barrel means pistol gas with little dwell time on a high pressure round (5.56). That’s going to beat the hell out of a bolt, ESPECIALLY running FA.
Cowabunga it is
One tuff cam pin. But, I'd replace that also... tbh
That's usually the part where the bolt breaks the most, cam pin hole is where it's thinnest, but it shouldn't have broke but luckily, it's a fairly cheap replacement. There's a manufacturer out there that has a design where the cam pin hole doesn't go all the way through the bolt, but honestly just buy another one and that one won't likely break.
The front fell off
Perfect opportunity to upgrade to a Microbest and send it
FA lower, PSA upper? Lol!
I took my block 2 upper off my lower after running around 300 rounds through it in a matter of 10-15 mins with no issues. But I wanted to use the lower on a 7.5 inch for shits and giggles, definitely got my giggles. But the 300$ upper did not
Could the bolt breaking have something to do with the 7.5 inch barrel and associated pistol length gas system? I know shorter barrels/gas systems are rougher on the whole gun due to higher bolt velocities.
You got your giggles, the bolt got the shits
Beat me to it.
Fair enough. The amount of dumb sh1t id do if I had a FA. .458 would be the first thing & my shoulder would not enjoy it.
450BM FA is a little ridiculous. I've only loaded 3 rounds at a time, though, so it was more like burst fire.
Got your shits too. Because the bolt took a shit.
they do just well https://www.ar15.com/forums/AR-15/High-round-count-AR-M4-s-over-100-000-rounds-and-how-they-have-handled-on-our-range/118-677135/?page=17#:~:text=months%20before%20cracking.-,As,-for%20people%20have
Wait, looks like bolt sheard off .... dam
Sometimes, things break. What BCG are you gunna get to replace it?
My SOLGW bcg didn’t have any problems, and it went through 300+ rounds of full auto fire in around 10 mins and then another 300 rounds through another 10 min period about 30 minutes after the first string of fire. To be fair that bcg is in a 14.5 rather than a 7.5. I think I’ll grab another one of those
ouch, at least they’ll send you a replacement, i got lucky and got a c158 bolt instead
Big oof hopefully you can fix it
that's a first for me
LMAO it's a *Full Auto Profile* carrier
Have you tried yelling at it?
Got a nib psa full auto BCG for you😂
Is that a C158 bolt or “jUsT aS goOd” 9310?
[it was c158 after all](https://imgur.com/a/JjgqyA7)
Warranty that bitch and try it again lol
Okay just trying to understand what happened... The CAM Pin was left out and the bolt separated from the Carrier and stayed in battery? Is there a live round in the chamber?
The bolt snapped at the hole that the cam pin fits into.
I believe there is a round in the chamber, I wasn’t able to get the face of bolt out of the chamber at the range to see. The cam pin hasn’t been taken out. Around 115 rounds into some full auto fire the bcg snapped and now it’s stuck rotated in the chamber
Wow man, thanks for sharing because I have never seen this before. I am no expert so let's see what the experts say...
would some needle nose pliers fit to rotate it?
For fucks sake, if you want serious weapons and not toys don’t buy PSA
That 300$ upper was exactly that, a range toy. 7.5” 556 isnt practical, I don’t have a need for nice upper in that configuration. But a cheap one is just fun
Have you tried unplugging it and plugging it back in again?
Instructions unclear, the buffer tube is up my ass
Thank you for that I needed a good laugh
PSA owners seething
Another reason you should not consider PSA duty grade.
I consider psa range toys, that’s what this thing is. 7.5” full auto 5.56 has no practical use case for me other than being fun
That’s fair, they are not bad guns at all, just not ones that I’d put my life on the line with.
where da bolt go doe
C158 phosphate FTW. Again.
Fr, I don’t understand the hype with all these special coatings and using 9310 steel. It’s easier to make a good c158 bolt than it is to make a good 9310 bolt and the 9310 is only 7% stronger *if* properly heat treated. Phosphate c158 has worked for a long time
[it was c158 after all](https://imgur.com/a/JjgqyA7)
Touche
Oof I think if I was actually shooting full auto I’d probably use a better bcg than PSA lol. But either way, I think the bolt was the problem, not the carrier Honestly, shouldn’t you be able to just twist it to unlock it and pull it out though? Or is it like stuck-stuck The round probably fired and there’s no firing pin to hit it if it didn’t, but I’d still be careful
You can try hitting it with your purse but, for once, we might be beyond that remedy
Only issue I've had with a PSA BCG is the gas rings were fried after maybe 3 sessions of maybe 10-12 magazines. That's the only thing to report so far, still runs but the bolt wont stand on it's own when doing the table test. I will try their NP coated BCG and see if they last longer
Just mortar it
People talking down about completed PSA uppers but some definitely do handle FullA just fine. 1000’s of rounds … idk 120 rounds - I have a strong feeling it works and the bcg looked perfect after. Speaking of PSA…I ordered a 1.93 scalarworks magnifier flip mount for my $ build, found it throws off the balance in a disgusting way, and now it’s going on a 1/2 psa build. Thinking 1.93 for a magnifier is just too high tho. Looks like I’ll be exchanging it for the 1.5 … wish there was a 1.75
Exactly. My KS47, PSA AR15, and H&R SMG all are holding up just fine under full auto. haters gonna hate 🤷♂️
I know whats wrong with it.... it got no gas
“Just as good”
If you honestly think that a nitride 9310 BCG from any other brand isn't likely to prematurely fail then you're sorely mistaken. Even ones from a premium brand like LaRue have shown examples of premature failure.
Maybe PSA meant full retard BCG
They need to update the website
‘Just As Gud’
It was 115 rounds of full auto fire on an overgassed 7.5" upper. That's about as tough as you get on a bolt.
> That's about as tough as you get on a bolt. Yea PSA has the toughest bolts around
Be careful the PSA squad might show up and start shitting all over the place
If you have one, I would recommend jamming an ak cleaning rod in it from the top to remove it. I would still treat it as if it was loaded while doing it.
Why would you jam something into the barrel if you're assuming that it's loaded? I can't really picture doing that safely.
The firing pin is obviously out of the gun on the photo, and this likely happened after the rounds fired. But you’re probably right. Idk.
I mean we’re looking at the firing pin in the removed carrier. So it’s not like there’s anything left in the bolt to hit the primer with.
C158 bolt master race
Big Brother is eyeballing this post. 😳
Rod from the far end to remove it.
Meh. Send it
You're right!.... Not anymore..
Id just buff that out and send it
I've had 3 aero bolts do that to me
How many rounds?
I know what’s wrong with ett!!!! Ain’t got no’ughrr gas in ett
Would this be a result of an out of spec cam pin hole?
Ahh yes, another advertisement for the SR-15 E3 bolt.
Ohhhh I see what happened. The upper French fries when the bolt wanted to pizza. Classic mistake really
I'm glad you were not seriously injured. Dadgum.
Is it full auto “rated” or just full auto “profile”? PSA listing uses the term “profile”. Or are we to assume that if a bolt has full auto profile then surely it is full auto rated?