Erratic Ejection Pattern

[JoeBobJoe]

Both of these problems are caused by a weak or marginal extractor spring.


Another victim of that thrice damned ejection voodoo chart. Your problem isn't how your AR is gassed. It's your extractor spring. Next time you suspect an AR is under gassed, perform a lock back check instead of consulting some ejection angle pie chart based on a witch doctor's interpretation of chicken entrails.


Because extraction with a rifle buffer & spring is softer. There's less stress placed on the extractor and you can get away with using a weaker extractor spring. in fact, the M16 extractor spring has a lower spring rate and will cause erratic ejection angles and bolt overs when used in carbine length ARs.

You can salvage your barrel with the over large gas port with a BRT gas tube. Contact Clint for help getting the right gas tube.

How can 2 Bolt carrier groups that work in other carbine uppers on carbine lowers both have weak or bad extractor springs? Also I tried it with O-ring without O-ring, because someone said it had too much extractor pressure. I did listen to the advice I've gotten. Why or how would another 16 in midlenth run fine with same BCG that chokes another? I tried the simple fixes first. I tested each BCG in my lady friends 16" middy & both were GTG.
Also both BCG are rather new under 1000 rounds a piece. A spikes tactical & a PSA premium. I'm got my H3 carbine buffer yesterday & I'm gonna run it tomorrow & if it runs on the carbine lower with the H3 like it did on the rifle lower, I'm calling it fixed.
Thanks for the advice, I do appreciate it. I'll post results tomorrow.

[MistWolf]

How can 2 Bolt carrier groups that work in other carbine uppers on carbine lowers both have weak or bad extractor springs? Also I tried it with O-ring without O-ring, because someone said it had too much extractor pressure. I did listen to the advice I've gotten. Why or how would another 16 in midlenth run fine with same BCG that chokes another? I tried the simple fixes first. I tested each BCG in my lady friends 16" middy & both were GTG.
Also both BCG are rather new under 1000 rounds a piece. A spikes tactical & a PSA premium. I'm got my H3 carbine buffer yesterday & I'm gonna run it tomorrow & if it runs on the carbine lower with the H3 like it did on the rifle lower, I'm calling it fixed.

You did see the part where I explained Spikes & PSA use substandard springs.

There are always small variations in lowers. An extractor spring nearing the edge of failure will often work with one lower and not in another. Until you install a Colt or M4 extraction spring in the bolt, you're wasting time and money. You've already tried more expensive remedies with no improvement. Why not try a $5 Colt spring?

Erratic ejection angles, weak ejection and bolt overs are only caused by weak ejector springs, bad extractors and/or weak extraction springs. Not magazines. Not feed ramps. Not short stroking. Not overgassing. Not recoil springs. Not buffers.

99 times out of 100, it's the extractor spring.

[JoeBobJoe]

I started by changing my lube from grease to oil because it was a cold day when it all started. Then extractor, then BCG, then extractor & ejection all checked to stop ftf bolt over base stoppages. Then I noticed ( because I am not a ejection pattern watcher)my ejection looked weaker than other 16 middy (AKA test/control AR) my friend lent me. My ejection pattern went from 1:00 to 2:00 with a lighter buffer (4 to 3 oz) ok...I filmed it slow motion & can see brass dribbling out & even getting hit by bolt on closing hence the 1:30 ejection with 4oz buffer & why the 3 oz made it go bit further (still only 2-3 feet in a falling dribbling motion) so on next solutions.
Mags, buffers, then gas leak test then tearing down gas system. Then find gas port was tight at .063, ok open up a hair, same results, then more .075 than a bit more, not much better & still ftf. I'm like "What the hell" , so me & my son (who has installed FSB for me) went for broke.... .093 & bang, better but still something wrong. .093 port & Rifle lower got me to 3 o'clock & 7 foot ejection & here I am.
That's my story. I didn't just start thinking drill baby drill from the start, I never even thought that was a option. I'm not afraid to try anything once, but don't expect to ever have to drill a gas port that again.
Thanks for listening.
J.B.J

[sinister]

You never mentioned your carbine manufacturer; whether or not this is a home built; how many rounds are down this barrel; and if, with the .093 gas port you still have stoppages.

Please, stop with the ejection distances and patterns -- that really has nothing to do with whether or not the weapon functions as designed.

Does it fire and go through the 8 steps of operation? If so, the carbine works. If not, help us help you to fix it.

[JoeBobJoe]

You never mentioned your carbine manufacturer; whether or not this is a home built; how many rounds are down this barrel; and if, with the .093 gas port you still have stoppages.

Please, stop with the ejection distances and patterns -- that really has nothing to do with whether or not the weapon functions as designed.

Does it fire and go through the 8 steps of operation? If so, the carbine works. If not, help us help you to fix it.

I did say it's my only Factory Built AR & it was bought new.
The brand is mid-level not a PSA or poverty poney.
I won't say because I was happy with their help & had other good experience with the company.
BTW, PSA is a good brand but I know some snobs look down on them.
I mentioned the ejection pattern as to give reference to what I'm trying to explain not because it's the cause of my concern. I got no problem with 1:30 ejection or even a weak or short distance of spent brass thrown. I clearly can see it's got a ftf & throwing brass different than any other AR I got or others I've seen in person. I checked the whole thing & know, see, & feel it's running like shit. I want it reliable or not at all. I would never sell a unreliable gun to anyone. Unless they wanted it as a project or to prove me wrong, I'm open to letting someone buy it to do so. I suppose I got the only unreliable AR. I'll go check the 8 steps for the 10th time, that'll fix her. Been there past that. I'm past farting into a glass & smelling it. I actually believe some people might know if their gun is not running correctly, & can check parts. Some just might keep trying to hit the fwd assist. I am not that guy.

Heavy buffer has no effect other than dropping cases at my feet, need to run more to actually check reliability.
Why does it run normally with the rifle lower and not with any carbine lower, normal meaning throws the brass clear of the weapon to 7 ft at 3:00 and not dribbles out at 1:30 to 3:00 and causes values to feed the rifle has not caused the fire to feed yet.
To me this is strange.

[JoeBobJoe]

I ran the H3 buffer and it ejects the casings at my feet, it went from ejecting cases 3 feet away at 1:30 to 2:30 with a 4 oz buffer,& now with the H3 buffer it's dropping cases at my feet; literally. With a lighter buffer (3oz) it gets ftf & 1:30 ejection about 3 feet. All with carbine lower.
The (16in midlenth) upper runs reliable with the rifle lower and ejects cases 7 ft away at 3:00.
Has anyone ever experienced anything like this? FTF were bolt over base & stove pipes, along with weak ejection.
I still need long term use on rifle lower to test reliability, but it looks good.
IDK
Thanks for anyone who replied with any information that they thought could help me, and to anyone who has a problem like mine I'd be interested to know if you were able to figure it out, or just what your experience was.
Thanks again.

[MistWolf]

Has anyone ever experienced anything like this? FTF were bolt over base & stove pipes, along with weak ejection.

I have. I told you where to start to fix it- the extractor spring. You ignored that. Your troubleshooting continues to be all over the map. Good luck getting your AR fixed. I'm sure if you continue to hit random keys on the typewriter, you'll eventually produce a sonata.

[JoeBobJoe]

[QUOTE=MistWolf;3029437]I have. I told you where to start to fix it- the extractor spring. You ignored that. Your troubleshooting continues to be all over the map. Good luck getting your AR fixed. I'm sure if you continue to hit random keys on the typewriter, you'll eventually produce a sonata.[/QUOTE

I have extra springs, I replace extractor springs if they feel weak. I get mine from Damage Industry, they are 4 coil gold (copper washed) I also run O rings most times. I will replace them with another new spring. I did things that didn't help 2 x over, just to make sure I was not missing something. The only trouble I've had with any extractor spring, was of my own making, the extra power 5 coil springs digging up my case head but went back to 4 coil. I ran the 5 coil with o ring & that is why I had trouble. I do learn from my mistakes. I'm gonna make a point to try a new 4 coil from my spare parts tomorrow. I can't get no more stumped than I am now.

[JoeBobJoe]

BTW the two BCG I been using run fine in a 16 in midlenth, home build. They just don't build em like I do.

[MistWolf]

These two steps should eliminate the extraction/ejection/feed problem-
-Install a Colt extractor spring with no O ring.
-Perform a flick test on the ejector. Installing a new ejector plunger and spring at this point is cheap insurance.

Next-
-Install an H2 buffer and carbine buffer in the lower (assuming you have a carbine RE).
-Test with full power 5.56 ammo. Start with a lockback test. Use a magazine known to be good.

Notes-
-Buffer weight will not fix over or under gassing. You must deal with the over-sized gas port before continuing troubleshooting. The easiest and least expensive way to do that is to get the proper BRT EZ Tune gas tube. Once this is done, you can resume troubleshooting. If you have further malfunctions after following the instructions above, they should be due to gas leaks and/or out of spec dimensions.