Erratic Ejection Angle + Bolt Locked behind Live Round

[Scout Actual]

Hello all,

I've got a problem I'd like some help with. I just recently built a new AR-15 from the ground up. My experience level is that I've built 2 AR's from the ground up (except drilling/reaming taper pin for FSB/Gas Block) and done modifications to a DD rifle. The parts of interests are Spike's Tactical with a DD Barrel, DD Gas Block, and Geissle SSA Trigger. Complete parts List below:
- Spike's Tactical FDE Stripped Lower/Upper combo (FA & Cover installed)
- Spike's Tactical LPK (minus fire control group)
- Spike's Tactical T2 Buffer, Buffer Tube, Spring, QD Receiver Plate, Castle Nut, Melonited Gas Tube
- Spike's Tactical NiB BCG
- Geissele SSA Trigger Group
- Daniel Defense Lightweight profile, Mid-length, CHF, Chromed, 16" 1:7 Barrel
- Daniel Defense Superior Suppression Device
- Daniel Defense Low Pro Gas Block
- BCM KMR13, Cerakoted Magpul FDE @ Dobb's Defense
- Magpul MBUS Sights
- Magpul STR Stock, FDE
- AXTS Raptor Charging Handle
- Troy Ambi Mag Release
- BAD-ASS Ambi Safety w/ Standard & Hybrid Lever
- Stark SE-1 Grip
- Vortex StrikeFire Non-Magnified Red Dot
- ErgoGrip Keymod Enhanced Angled Grip
- Noveske QD Direct Attach Swivel Mount

I took it out for the first time yesterday and at first I thought everything was fine. However I had two instances of the same failure (in a total of about 200 rounds fired). During a string of fire (perhaps 0.5 seconds between rounds, plenty for everything to settle) I had the bolt lock up in a mostly closed position. The bolt is about 1/8" out of battery. There was a live, unfired, round in the chamber at this time. The field expedient fix was to mortar the gun to let inertia loosen the bolt.

Luckily a friend happened to be filming me while this happened. See slow-motion, 240 FPS, Dropbox video below (pay no mind to my terrible trigger reset... I'm a relative newb). Also I've screen-grabbed & cropped a pic of the bolt in battery during normal operation and out of battery (basically the failure) shown below.

Dropbox: Slow-Motion 240 FPS Video

In Battery Photo
Out of Battery Photo

Speaking to a few guys at the range a conclusion was reached that, in the failure case, the bolt is closing on the round without the extractor making it over the rim of the cartridge but is rotating enough be stuck. Some suggested that there might be wrong with the extractor spring and that it should be replaced. Since it is such a cheap fix I already have new springs (mil-spec Spikes in old case, David Tubb springs in the new case) on order.

After looking at the video evidence it is also obvious that I've got erratic and inconsistent ejection. Sometimes the rounds eject at 5 O'Clock with little rotation, sometimes they eject at 2 O'Clock with lots of rotation and everywhere inbetween. Could these 2 problems be related? Could the gun be undergassed and that is why the extractor sometimes doesn't make it over the case rim?

Thanks in advance!
Scout

 

[1006]

Did you try the forward assist to close the bolt?

What ammo were you using?

I wonder if enough gas is getting to the bolt.

My factory AR ejects in every direction as well. It depends on consistent ammo and firmness of hold on the gun. I would not pay much attention to the ejection pattern for anything more than than a general indication of ejection strength.

Good luck with it.

 

[Scout Actual]

The ammo was remanufactured brass .223. I plan on going to an indoor range this week with 2 different brands of remanufactured ammo and 1 brand of factory ammo and film/compare the ejection patterns (and of course look for the bolt locking up).

 

[dial1911]

Also need to check the fired brass... do some have a really heavy extractor mark on the rim? Is the ejector making a noticeable shiny spot on the base, or is it possibly causing a dent or gouge?

I'd also look at the locking lugs on the bolt to be sure there's nothing noticeable there.

 

[Scout Actual]

Lugs look fine as far as I can tell. I will keep an eye on the brass next time I go to the range.

 

[mtdawg169]

The ammo was remanufactured brass .223. I plan on going to an indoor range this week with 2 different brands of remanufactured ammo and 1 brand of factory ammo and film/compare the ejection patterns (and of course look for the bolt locking up).

First, DD barrels are rarely, if ever undergassed. My first suspicion would be the reman ammo. The varying ejection pattern could be a result of inconsistent powder charges. A light load may be on the verge of short stroking. OR there could be an issue with the BCG.

Another possibility is that the rounds may be loaded a tad long on OAL or the remote possibility is a chamber issue. The fact that it was not fully in battery and you had to mortar it to remove the round, is very concerning. This points to the ammunition as a likely cause.

Shoot the gun with a few hundred rounds of known good, milspec ammo and report back.

Also, if you're running a donut under the extractor, remove it.

 

[rOmiLaYu]

[Broken External Image]:

 

[DMGun]

Thought this was about Erotic Ejaculation at first glance on "The Feed"... Need more Sex....

 

[mtdawg169]

Why are my cool shades crooked? Might need to get my ears checked for alignment...

 

[mtdawg169]

Hello all,

I've got a problem I'd like some help with. I just recently built a new AR-15 from the ground up. My experience level is that I've built 2 AR's from the ground up (except drilling/reaming taper pin for FSB/Gas Block) and done modifications to a DD rifle. The parts of interests are Spike's Tactical with a DD Barrel, DD Gas Block, and Geissle SSA Trigger. Complete parts List below:
- Spike's Tactical FDE Stripped Lower/Upper combo (FA & Cover installed)
- Spike's Tactical LPK (minus fire control group)
- Spike's Tactical T2 Buffer, Buffer Tube, Spring, QD Receiver Plate, Castle Nut, Melonited Gas Tube
- Spike's Tactical NiB BCG
- Geissele SSA Trigger Group
- Daniel Defense Lightweight profile, Mid-length, CHF, Chromed, 16" 1:7 Barrel
- Daniel Defense Superior Suppression Device
- Daniel Defense Low Pro Gas Block
- BCM KMR13, Cerakoted Magpul FDE @ Dobb's Defense
- Magpul MBUS Sights
- Magpul STR Stock, FDE
- AXTS Raptor Charging Handle
- Troy Ambi Mag Release
- BAD-ASS Ambi Safety w/ Standard & Hybrid Lever
- Stark SE-1 Grip
- Vortex StrikeFire Non-Magnified Red Dot
- ErgoGrip Keymod Enhanced Angled Grip
- Noveske QD Direct Attach Swivel Mount

I took it out for the first time yesterday and at first I thought everything was fine. However I had two instances of the same failure (in a total of about 200 rounds fired). During a string of fire (perhaps 0.5 seconds between rounds, plenty for everything to settle) I had the bolt lock up in a mostly closed position. The bolt is about 1/8" out of battery. There was a live, unfired, round in the chamber at this time. The field expedient fix was to mortar the gun to let inertia loosen the bolt.

Luckily a friend happened to be filming me while this happened. See slow-motion, 240 FPS, Dropbox video below (pay no mind to my terrible trigger reset... I'm a relative newb). Also I've screen-grabbed & cropped a pic of the bolt in battery during normal operation and out of battery (basically the failure) shown below.

Dropbox: Slow-Motion 240 FPS Video

In Battery Photo
Out of Battery Photo

Speaking to a few guys at the range a conclusion was reached that, in the failure case, the bolt is closing on the round without the extractor making it over the rim of the cartridge but is rotating enough be stuck. Some suggested that there might be wrong with the extractor spring and that it should be replaced. Since it is such a cheap fix I already have new springs (mil-spec Spikes in old case, David Tubb springs in the new case) on order.

After looking at the video evidence it is also obvious that I've got erratic and inconsistent ejection. Sometimes the rounds eject at 5 O'Clock with little rotation, sometimes they eject at 2 O'Clock with lots of rotation and everywhere inbetween. Could these 2 problems be related? Could the gun be undergassed and that is why the extractor sometimes doesn't make it over the case rim?

Thanks in advance!
Scout

A couple of additional thoughts. First, for an admitted "newb", you wear a **** ton of kit to the range.

Second, I can rule out any chamber tolerance issues for you if you would like for me to inspect the upper.

Third, this is the second issue I've seen reported this week that involved a Spikes NiB BCG. Second only to the unknown reman ammo you were using, the BCG would be the next most likely cause. Advice: don't waste your time with NiB.