PDA

View Full Version : Pictures of BCG. Had A FTE Party Yesterday. Help Is Needed


The1stWright
04-08-2012, 4:54 PM
Well as many of you already know I shot my new AR15 upper yesterday. I had 13 FTE's during the whole shooting process. Many asked for pictures of the BCG to help me diagnose the problem. Here they are!

http://i1120.photobucket.com/albums/l485/immrwright7/photo-18-1.jpg
http://i1120.photobucket.com/albums/l485/immrwright7/photo-19.jpg
http://i1120.photobucket.com/albums/l485/immrwright7/photo-20.jpg
http://i1120.photobucket.com/albums/l485/immrwright7/photo-21.jpg
http://i1120.photobucket.com/albums/l485/immrwright7/photo-22.jpg
http://i1120.photobucket.com/albums/l485/immrwright7/photo-23.jpg
http://i1120.photobucket.com/albums/l485/immrwright7/photo-24.jpg

FourLoko
04-08-2012, 5:00 PM
what's up with the gas rings? you got toothpaste on there?

kendog4570
04-08-2012, 5:01 PM
A little lube might help.

Emphasis on the word "little".

The1stWright
04-08-2012, 5:07 PM
what's up with the gas rings? you got toothpaste on there?

Lol nope, might be the flash.

The1stWright
04-08-2012, 5:08 PM
A little lube might help.

Emphasis on the word "little".

I dried it off to take pictures. It was well oiled prior to shooting

HK Dave
04-08-2012, 6:24 PM
Take apart the bolt, lets have a look see inside it.

The1stWright
04-08-2012, 6:33 PM
Ok I'll take it apart now

Hoop
04-08-2012, 6:40 PM
I had one that was not ejecting the old case and trying to feed a new one (doublefeed, stovepipe however you want to term it) and a new extractor spring fixed the issue.

E_Shaw90
04-08-2012, 7:17 PM
Pull the extractor away from the bolt...feel the extractor face by rubbing a finger tip across it.... It should feel like 2 kitten teeth. Make sure the extractor spring and buffer are in place. If that checks out make the ejector is working...reassemble the extractor to the bolt...use a spent (empty) case and place it in the bolt face....there should be a decent amount of resistance. That it pretty much all you can try... If some of the above is not present replace the parts. If you find nothing try swapping out with different BCG and see if the problem goes away. If your still stuck and are in the Sac area I can help ya

GMG
04-08-2012, 7:47 PM
I had one that was not ejecting the old case and trying to feed a new one (doublefeed, stovepipe however you want to term it) and a new extractor spring fixed the issue.

Your on to something there ! I had the same problems and put a BCM extractor spring kit in and solved my problems.

http://www.bravocompanyusa.com/BCM-Extractor-Spring-Uprade-Kit-p/bcm%20extractor%20spring%20%203pack.htm

supermario
04-08-2012, 9:33 PM
Is it me or does it look like the gas key is not properly staked?
If you look at the first pic, isnt the gas key and screws suppose to both be
dented (staked), to me it looks like only the gas key is dented but the actual screws are not touched? Maybe just my eyes?

pingdork
04-08-2012, 10:31 PM
I thought same thing as supermario. Not sure if bad staking job would be the cause of your issues tho, but it's not a good sign

supermario
04-08-2012, 10:33 PM
I would think if its not properly staked, then the gas key can still come loose and create problems right?

OP, what type of BCG is that?


I thought same thing as supermario. Not sure if bad staking job would be the cause of your issues tho, but it's not a good sign

digdug74
04-08-2012, 11:14 PM
I don't know, man -- it might just be the camera flash, but that bolt not only looks crudely manufactured, but filthy to boot. Looks like there might be enough crud in there to have partially seized up the ejector...

You might want to completely disassemble the bolt and clean the crap out of it. Once you've got it clean, reassemble it and check the ejector spring tension. It's hard to describe what you're looking for here -- the ejector pin should be hard to depress but once you've hit the right amount of pressure, it should go back into the bolt fully and come back out fully with little friction.

peter95
04-08-2012, 11:26 PM
Is it me or does it look like the gas key is not properly staked?
If you look at the first pic, isnt the gas key and screws suppose to both be
dented (staked), to me it looks like only the gas key is dented but the actual screws are not touched? Maybe just my eyes?

I'm sure If the gas keys was lose, OP would have noticed. Being staked is good but if on proper specs, torqued down it should be ok also.

Check the spring in the bolt, see if it's not longer good.

tradecraft
04-08-2012, 11:27 PM
What brand is the upper/BCG? That thing looks nasty for a day-old part.

The1stWright
04-09-2012, 1:32 AM
No stamps saying what model the BCG is I'm going to take it apart, clean it up really well. And shoot again. If that doesn't work I might have to look into replacing the BCG all together. One quick question though, which way is the extractor supposed to face upon reassembly?

rojocorsa
04-09-2012, 1:49 AM
Don't mean or want to sound redundant, but your buffer weight is good to go, right?


which way is the extractor supposed to face upon reassembly?
http://www.gunblast.com/images/50Beowulf/Mvc-008f.jpg

sdfire
04-09-2012, 4:38 AM
Try a different bolt carrier assembly, then if the problem continues, check the gas tube / gas block for obstructions . Otherwise I would start with the extractor spring .

scotty99
04-09-2012, 6:08 AM
I'm a little surprised no one has asked, but what ammo were you using? Have you tried different ammo and been able to replicate the problem?

Also, with the BCG out of the weapon, will a round slip easily in and out of the chamber?

mcisniper
04-09-2012, 7:58 AM
I agree with scotty99 and sdfire.

What type of ammo and how many rounds did you fire?

Did it try to extract or was it running like a bolt gun (Fire a round and manually cycle)?

Michael

ProlificARProspect
04-09-2012, 8:53 AM
Your on to something there ! I had the same problems and put a BCM extractor spring kit in and solved my problems.

http://www.bravocompanyusa.com/BCM-Extractor-Spring-Uprade-Kit-p/bcm%20extractor%20spring%20%203pack.htm

this!

Get the BCM extractor upgrade kit with O-ring and spring. That's all you need.

Uruz003
04-09-2012, 9:34 AM
I would also recommend taking a look at the spent casings, particularly the ones that failed to eject. If if you notice little to no extractor marks on them, it is a strong indication that you have a weak extractor springs or a faulty extractor. For this I would support the previously mentioned extractor kits. Failing that you could look into the extractor, but I don't have much experience in that area.

- URUZ

The1stWright
04-09-2012, 9:54 AM
Thanks guys for helping me. As you can see i'm a complete AR newb. I really appreciate this. I was using PMC ammo. 55gr. .223 I didn't see any marking on the spent casings, so it might be a weak extractor. I guess that will be the first step I'll take in solving the problem. It seemed to be that the bolt would recycle too fast because the spent casing would be directly on top on the bolt, and the live round would basically be directly underneath.

Uruz003
04-09-2012, 10:38 AM
Can you possibly get a picture of the failure? I'm not sure I fully understand the nature of the FTE. Is the spent shell still in the chamber while the bolt pushes a fresh round up against the feed ramp?

The1stWright
04-09-2012, 10:40 AM
I'm out of ammo so I cannot get a picture of the failure but the way you described it is excatly how it happened.

Uruz003
04-09-2012, 10:41 AM
Ah, had this problem with my AR. In my case it was a weak extractor. I'm fairly confident that replacing the extractor and springs would fix it. Hope it works.

The1stWright
04-09-2012, 10:49 AM
Thanks I'm going to buy one put it on my AR and give it a shot. I hope that solves the problem.

almaster666
04-09-2012, 10:51 AM
lube it and shoot it a lot.
Mine wouldn't lock back on last round for the first few hundred rounds that I shot.
There is such a thing as breaking in your rifle

glock7
04-09-2012, 2:08 PM
I'd shoot something a little hotter. Pmc tends to be on the weaker side. Try shooting different ammo before you do any investing. And that bolt looks clean. I did a 1000 round without cleaning when I first got my bcg, just kept it lubed and it ran fine. It was a beeeotch to clean. Also check your buffer as advised, before you buy an extractor. Although its good to have extras. Good luck.

The1stWright
04-09-2012, 3:04 PM
What should I be checking for as far as the buffer? Also what ammo should I shoot the next trip?

I'm also working on sighting in my MBUS flip up sights before adding an optic. But my question is how do I adjust the front sight?

Johnnyfres
04-09-2012, 3:33 PM
Get this and you wont have anymore issues :D

http://www.bravocompanyusa.com/BCM-Bolt-Carrier-Group-MPI-Auto-M16-p/bcm%20bolt%20carrier%20group%20auto%20mp.htm


Front Site Tool.
http://www.riflegear.com/p-403-midwest-industries-a2-sight-tool-wrench.aspx


Also look up zeroing your rifle with iron sites.

hollowpoint
04-09-2012, 4:53 PM
Whats your buffer weight? Weaker ammo likes a skinny (carbine) buffer. The combination of weak ammo and a heavy buffer would result in the type of problem you are having.

The1stWright
04-09-2012, 6:13 PM
I bought the lower fully assembled so I have no idea what the weight is

SURVIVOR619
04-09-2012, 6:26 PM
Whats your buffer weight? Weaker ammo likes a skinny (carbine) buffer. The combination of weak ammo and a heavy buffer would result in the type of problem you are having.

Not the thread jack, but this is one of the better, more concise responses I've read about buffer differences. Thanks hollowpoint.

AJ27
04-09-2012, 6:41 PM
I bought the lower fully assembled so I have no idea what the weight is

Im pretty sure what they mean by "buffer weight" is what kind of buffer do you have in your stock? If you open your AR up you can see the buffer inside the buffer spring all inside your stock and if you push in the little detent it will come out so you can check... I have a spikes tactical T2 heavy so on mine it says ST-T2 not sure what lower you have but you can Google it to find out.