There's a crack in my brand new BCM bolt carrier's

>>33688159
I don't see a crack. "Staking" involves deforming a small amount of metal toward the surface and has nothing to do with the structural integrity of the underlying metal that wasn't deformed.

>Should I be worried
No
>Should you send it back?
I know I would

Is this real or am I getting rused? That's called staking.

>>33688159
got a better picture? I don't see a crack.

File: Fracture.jpg (18KB, 450x280px) Image search: [Google]

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THIS is a crack, you idiot

>>33688159
That bolt is unsafe to shoot anon.

>>33688202
nevermind, I see it now.
I wouldn't be worried if it were mine.

I see what he's talking about.

When the bottom screw was staked, a bit of it cracked on the outside.

>>33688159
I see the crack but its probably fine, return it if you paid a lot or its a reasonable company

>>33688218
The metal is ruptured, but the bolt isn't cracked.

Nah, it's just the gas key, they stake them to keep retards from disassembling it, there isn't gonna be a lot of stress on that part.

>>33688159
no quit overreacting

>>33688246
I always heard they were staked to keep them from jiggling loose as the bolt slams back and forth thousands of times.

>>33688204
that's a fracture.

>>33688179
>>33688159

if you try to send it back, good luck anon

i have 3 bcm uppers and a variety of parts from them. A buffer tube assembly I got from them was missing nearly half of its anodizing on the inside. When I contacted them for a replacement they told me to eat shit. Is it a cosmetic issue? yes. Do i expect to get what i (over)paid for? also yes.

feels good to be out of the ar build game and not deal with bs anymore tho

>>33688294
Multifunctional.

>>33688204
>file name

>>33688286
The dude is wearing gloves to build an AR.

You can't tell him that.

>>33688541
yo maybe he doesn twant to get greasy hands

>>33688541
IKR, that shit always cracks me up.
>better wear gloves, wouldn't want to get some harmful grease or oils on my hands while building this
>builds it, then goes to the range and shoots lead filled bullets propelled by gases made by many different burning chemicals, lit off by a compound made of mercury.
yeah, anon. good call on those latex gloves for the little bit of oil you might get on your hand

>>33688159
Bcm quality everone

>>33688541
>>33688656
>>33689056

Maybe he doesnt want finger prints left behind? I do it all the time when loading my conceal. If shit goes really really wrong (brass cleanup) I want to know all options are on the table.

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>>33689070

>>33689145
I guess if you go around committing robberies that's the way to go.

>>33689056
>mercury
Mercury hasn't been used in primers anywhere in the world since 1949 and hasn't been used in non-Russian/Soviet-bloc countries since 1896.

File: themoreyouknow.gif (206KB, 299x189px)

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>>33689480
Thanks.
That doesn't really change my point though.

>>33688159
You should. That crack, after being subjected to high amounts of pressure, will cause the staking to explode, potentially making your AR-15 assault rifle into an explosive device.

>>33689056
I wear gloves when I'm cleaning stuff. Not from fear that the grease or oils will harm me, but to avoid making a mess. If the phone rings or I'm otherwise prompted to quickly leave and do something else, it's easier to remove some gloves than it is to properly wash the dirt off my hands before I handle something that I don't want to get dirty.

>>33688159
id send it back if only for piece of mind. every time you shoot it, youll think of that tiny split and itll always be in the back of your mind

>>33689541
Yes it does. You explicitly stated that the process of firing a bullet releases toxic gases and particles, including heavy metals, into the vicinity of the shooter.

That's flat-out untrue.

>>33689691
His point was that he thought the OP was being excessively cleanly. The stuff about the toxic gasses was his shitty strawman that he built in an attempt to support his point.

>>33689720
AKA, he lied out his ass to make himself feel better.

>>33688159
Send that bullshit back. For what you're paying there's no fucking excuse for them to be sending that out the door.

>>33688420

Kill yourself

>>33689691
>>33689720

Just because primers don't have mercury doesn't all of the sudden make firing guns perfectly healthy you shitlords. The process of firing a bullet literally releases toxic gases and particles, including heavy metals, into the vicinity of the shooter. It might not release atomized mercury, but it certainly does all the others.

Read the warnings on the back of your ammo boxes. It specifically tells you to fire with adequate ventilation. They're not worried about you running out of air to breathe, they're warning you about breathing the discharge. Why do you think indoor ranges have fans? To stop you from sweating through your rainbow dash shirt?

>>33689928
Start naming them.
>heavy metals
Lead is not a heavy metal, and is not released upon FIRING a bullet. If the bullet fragments against a backstop or something THAT might release some, but the act of firing it does not.
>chemicals in gunpowder
Gunpowder consists of nitrocellulose, graphite as a stabilizer, maybe nitroglycerin if it's a shotgun or pistol powder, and a bunch of other nonreactive nonhazardous additives for temperature sensitivity reduction. The SDS are literally available online for every powder available in the first world. I mean shit, it doesn't even produce carbon monoxide when burned, just CO2, and in literally miniscule amounts.

You're fucking wrong and I can literally prove it.

>>33688204
am I being trolled

that is clearly a stress fracture

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>>33690100

>>33689846
wew lad, put down the edge.

>>33689145
Criminal.

>>33690100
If you feel the need to correct someone you should probably make sure you know what the fuck you are talking about.

>>33688177
and since there's no stake its not staking its SWAGING

fucking mall ninjas

>>33690100
have you ever been to a shitty old indoor range and wiped the palm of your hand across something at the firing line?

>>33690262
Yes.
>contains graphite
Nigger can you read?

Is graphite a heavy metal?

Is graphite in any way toxic or poisonous?

No. It's fucking inert particulate.

>>33690176
https://www.hodgdon.com/wp-content/uploads/2016/11/clays-as30n.pdf
There nigger. There is the MSDS for one of the most common powders on the market and which is OEM for all of ATK and UMC.

Go line by motherfucking line and highlight all the heavy metals or toxic gases.

>>33690415
Lead is a heavy metal.
Lead styphnate is the most common primer formulation.
Clays is not exactly a common powder. Even then nitroglycerin and its combustion products are toxic.
Most powders contain burn rate modifiers like Diphenylamine and N,N'-diethyl-N,N'-diphenyl-urea. Again these and their products are toxic and are currently being phased out to less toxic alternatives.

File: vhyuqw94.jpg (13KB, 266x450px) Image search: [Google]

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>>33690397
Man, bullets are so eco-friendly...they should invent and engine that could run on gun powder.

Going green, one muzzle blast at a time.

>>33689846
t.BCM Customer Service Rep

>>33688159
What is going to happen if that isn't structurally sound? Nothing. It is fine.

>>33688159
>Should I be worried?

Let me tell you how metal works, OP.
That crack is because the metal there would rather open up than stretch. Metal is very lazy and will take the easiest way out.

There is literally nothing wrong.

>>33688159
Just run an eddy current test and check to see if there is a break. Looks more like an eyebrow on their swage. Alternatively, you could run an acoustic imaging test, but I doubt you have ultrasonic transducers for it. Lastly, you could do a magnetic particle inspection, but that requires a specialized machine.

>>33688159
You twat. The surface of the metal (parent material) can crack like that from staking deforming it.

Don't schools teach shop anymore?

>>33688541
lol

>>33692642
>There is literally nothing wrong.

Unless it's a crack in a part that experiences fatigue loading, then the crack is going to propagate until it fails.

>>33688362
>>33690115
Not that guy, but it's generally referred to as a crack when it hasn't separated and a fracture when it has.

t. Mechanical enguneer specializing in fatigue and fracture mechanics

>>33693568
Also, I should add, this picture is bad form. You NEVER put the samples back together after fracture

>>33693416
>Don't schools teach shop anymore?

No.

>>33688159
OP, that looks like a rupture caused by the staking process. The loads that part of metal have to bear (the screw trying to back out of its place) wouldn't cause it, nor would those loads exacerbate it. In other words, I wouldn't worry about it.

>>33688159
Don't feel bad OP, I'm OCD too when it comes to gun stuff. Just leave it alone it's fine.

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>>33690100
>Lead is not a heavy metal

Heavy metals are generally defined as metals with relatively high densities, atomic weights, or atomic numbers. The criteria used, and whether metalloids are included, vary depending on the author and context. In metallurgy, for example, a heavy metal may be defined on the basis of density, whereas in physics the distinguishing criterion might be atomic number, while a chemist would likely be more concerned with chemical behaviour. More specific definitions have been published, but none of these have been widely accepted. The definitions surveyed in this article encompass up to 96 out of the 118 chemical elements; only mercury, lead and bismuth meet all of them.

>>33693416

I have never done anything like that except for sawing bits of wood when I was... 12? I can't say I've ever been taught anything about metal.

>>33690100
>Lead is not a heavy metal
Please kill yourself, you're too stupid to live.

test

>>33695225
The gas key is fine. Reading this thread...I just don't know what to say. I get a lot of you guys don't know any better.

How many here stake their own end plates? Notice a similar effect depending on how cheap of a one you get?

Gas keys get heat treated differently by each manufacturer. A lot of manufacturers just outsource it. I have seen gas keys come in really fucked up from a miscommunication in the process. As long as the key rest in the carrier nicely and is straight, I wouldn't worry. Your gas tube alignment and even wear on the gas tubes flange while going in and out of the key is what you all should focus your attention on every are you buy or build.