AR15.Com Archives
 New build not ejecting
rushmc  [Member]
10/23/2011 8:48:27 AM
Templar lower
colt 14,5 inch barrel
DPMS carrier and bolt
AA upper
AA lowpro gas block

All functions fine using the charging handle


Ok
I did the search thing here
I have read all the suggestions and all the found problems
I have few things to check out but I have another question
I have JP Enterprises flat music wire spring and and H2 buffer.

Have I overkilled the system?

Thanks

Marc
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Dano523  [Moderator]
10/23/2011 11:20:59 AM
Clean and lube it, load a single round of the ammo you will running into a mag, insert the mag and charge the round, then fire for effect.

If you have over sprung or the buffer is too heavy for the rig, the bolt is not going to lock back, hence the rifle will short stroking.
Gatorhunt  [Team Member]
10/23/2011 11:24:17 AM
When you say "not ejecting" do you mean the spent case is left in the chamber or that it's "stove piping" or leaving the the spent case in the action somewhere?
rushmc  [Member]
10/23/2011 12:25:11 PM
I did not think of that test but

I had a chance to read much more here after I posted

I cleaned it (again) and used a lube I have used before ( tried a new one on this build)

Put a bit more lube on the buffer spring and took it out and tried it

This time it would eject the case about half the time.

It is also going far enough to set the trigger every time but never far enough to pick up a new round

I will try your test later

As to the other question

It is just not opening far enough to eject the case

It is still in the bolt when I pull the handle and it kicks it out just fine.

There is some GREAT info here

I dropped off for a while after I sold my 223 and build a 6.5 Grendel (which I love)

But then I realized I needed the 223 for other reasons.


I look forward to more suggestions and advice

Thanks to all
rushmc  [Member]
10/23/2011 12:28:24 PM
It is leaving it in the bolt

Pull the handle and it kicks it out just fine and loads another round

So, if I am over sprung along with the H2 buffer, which would make the most sense to replace

(BTY, I am going to buy both and try different combinations. Cant have too many parts laying around you know)
azarby  [Member]
10/23/2011 9:23:55 PM
Try a regualr carbine buffer. You could also be under gassed. Make sure you gas block is centered correctly and is on tight. Also check your gas key on the bolt carrier to make sure the screws are not loose
vhunter  [Team Member]
10/23/2011 9:38:02 PM
Originally Posted By azarby:
Try a regualr carbine buffer. You could also be under gassed. Make sure you gas block is centered correctly and is on tight. Also check your gas key on the bolt carrier to make sure the screws are not loose


+1 check gas block alignment
rushmc  [Member]
10/24/2011 7:48:57 AM
I will check the block again

So if the gas block is correct, do you think the spring and buffer combo I have should work?

Thank

Marc
madcratebuilder  [Member]
10/24/2011 8:03:35 AM
I have JP Enterprises flat music wire spring and and H2 buffer.


Too much spring and buffer. Test the carbine with the standard spring and buffer, then try with a H buffer. A H2 and a higher tension spring would choke my carbines.
rushmc  [Member]
10/24/2011 9:37:53 AM
That has been my guess as well

Easy einough to test

Thanks everyone

Oh

And thanks to those who really know these machines

The "how they work" threads on this site are better than great!!
rushmc  [Member]
10/26/2011 7:47:01 PM
Update;

Standard spring standard buffer installed

Functions flawlessly

Will tune with the parts in the future

Thanks to all who helped

Marc
rushmc  [Member]
10/28/2011 10:27:22 AM
Update

Took it out again and the bolt lock stopped working

Found the bolt lock to be loose because the roll pin fail

I think this rifle may be possed
rushmc  [Member]
11/2/2011 8:01:12 AM
Originally Posted By madcratebuilder:
I have JP Enterprises flat music wire spring and and H2 buffer.


Too much spring and buffer. Test the carbine with the standard spring and buffer, then try with a H buffer. A H2 and a higher tension spring would choke my carbines.



I am going to go play later but I was curious as to what you have found to be the best combos of springs and buffers

I know this can be very specific to the set up but I am wondering whay your experience has taught you

I am going to try the heavier spring with the standard buffer and the standard spring with the H2 buffer (I have had the later before and it really made the gun run smoother

Looking forward to your thoughts

Marc
sorral  [Member]
11/8/2011 11:05:50 PM
From what I am reading I am having a similar issue. My rifle has been having problems since I built it (all from parts, no kit).
Gun will fire fine with slow steady fire, but when I up the volume down range every so often I get a stove pipe. It drives me nuts! We have checked the following:

1. Ammo, different brands as well as reloads
2. Magazines of all types and brands
3. No excessive carbon anywhere
4. I put my upper on my gunsmith's lower, no difference
5. Put gunsmith's BCG in my rifle, no difference
6. Changed rings and extractor springs on bolt
7. Gas tube is new and clear
8. Ports on barrel and gas block are clean and clear
9. The whole rifle is kept pristine clean and lubed properly.

I do notice that my firing pin retention pin does get really banged up and needs replacing about every 200 rounds, I am not sure if this is a problem, just tossing it out as a potential symptom. We have ruled out the BCG, Buffer and spring, Ammo, and lubrication. My only thought now is the gas system. I see no signs of gas leaks around the gas block (no carbon build up). It just seems when the thing heats up, it malfunctions.

I hope one of you out there can help, I have two gunsmiths scratching there heads and apologizing to me, and I can not afford to just swap parts until it works.
sorral  [Member]
11/9/2011 12:37:51 AM
I have been doing some internet searches, and have come up with an idea about my problem. Another symptom I did not mention was my brass had heavy extractor markings. This with the damaged firing pin retainer, and the extraction issues seems to point to too much gas pressure. The high pressure is causing the bolt carrier to try to rip the spent case out of the chamber before the case has a chance to recover from the pressure of being fired, causing the extractor to take a hard bite on the case rim. This heavy pressure also is a hard blow to the gas key, and the sudden slow down is causing the firing pin's inertia to bang the retainer pin. The case being still too large to extract smoothly, slows the BCG and causes the stove pipe....At least this is what I understand from a few Google searches...


Does this all seem plausible to anyone else?
Gatorhunt  [Team Member]
11/9/2011 10:10:50 AM

Originally Posted By sorral:
I have been doing some internet searches, and have come up with an idea about my problem. Another symptom I did not mention was my brass had heavy extractor markings. This with the damaged firing pin retainer, and the extraction issues seems to point to too much gas pressure. The high pressure is causing the bolt carrier to try to rip the spent case out of the chamber before the case has a chance to recover from the pressure of being fired, causing the extractor to take a hard bite on the case rim. This heavy pressure also is a hard blow to the gas key, and the sudden slow down is causing the firing pin's inertia to bang the retainer pin. The case being still too large to extract smoothly, slows the BCG and causes the stove pipe....At least this is what I understand from a few Google searches...


Does this all seem plausible to anyone else?

It is true that over pressure can cause those types of symptoms....




It could be the gas port in the barrel is a little over sized, can you pull the GB and measure the port size?

A heavier buffer can help to slow things down a bit but doesn't always solve the problem, might need an adjustable gas block or gas tube to tweak the pressure to where it needs to be.
sorral  [Member]
11/10/2011 10:44:57 AM
The gas block was pulled, and the barrel port was checked. It is within specifications. The gas tube fits correctly into the gas block, The only thing out of the ordinary (aside from the stove pipe when hot) is the fact that the original gas rings got chewed up after less than 1000 rounds, and the firing pin retention key only lasts about 200 rounds. I did, after reading the answers I have gotten, think the culprit may be the fact that the only part I cheaped out on was the butt stock assembly. It is a $35 UTG setup. I wonder if the buffer and spring are too light. To check I put my upper on my buddy's lower, same problems.
occasionalvisitor  [Member]
11/12/2011 3:11:45 PM
I suspect that you have more than one problem.

Is your bolt carrier an unshrouded semiauto carrier? That would explain the damaged firing pin retainer pin. The bolt rings getting torn up in a 100 rounds would suggest that the bolt carrier was not machined properly. I would suspect that if you check the bolt passage in the bolt carrier, you will find some burrs left from machining. I would recommend replacing the complete BCG with a better quality part (I like the PSA Premium BCG that I bought on sale for $99 each earlier this year).

Clean the chamber throughly, and look for defects that would hamper extraction, and try a standard carbine buffer.
sorral  [Member]
11/12/2011 8:08:25 PM
update:

My gunsmith and I took the rifle out yesterday, we took 3 different brands of factory ammo, my reloads, and reloads of progressively lower powder charges. We chronographs the results and compared my rifle to his. My gun was shooting about 300fps slower than his on all rounds tested. The barrel was used (he gave it to me), and he determined that it was probably worn out (has about 25000-30000 rounds.) The gas block was leaking, I am going to order a new barrel next week, we are also going to take out the high power spring from the extractor and up the normal one in. Hope this solves all my problems!
sorral  [Member]
11/23/2011 4:26:28 PM
new update

I put a new barrel on my AR last night, got a nice one from Midway USA. I took the rifle out this morning and test fired it. I started slow fire with 10 factory rounds, then 20 rounds of factory ammo at a moderate pace. I finished with 20 rounds of my reloads rapid fire, as fast as I can pull the trigger. NOT ONE FAILURE!
hondamx518  [Member]
11/26/2011 10:27:06 AM
wow! that will do it. thats a lot of rounds
sorral  [Member]
11/27/2011 6:34:55 PM
UPDATE:

My brother and his family came up from California for the holiday weekend. We took everyone out shooting yesterday and put another 130 rounds through the AR, still no failures. We even took turns paying Tony Montana, "Say Hello to my lil' frien'" and pull the trigger as fast as possible from the hip, a lot of fun for the kids!
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