I need your help on this one.  I have two malfunctions with my AR-15.  One of these is constant and the other is a current problem caused by the first.  Here is a build list of my AR-15:

1. Model-1 Sales 7.62x39 Carbine 16" AR-15A4 post-ban upper
2. Eagle Arms 5.56mm lower receiver
3. Post-ban CAR buttstock

The following is a description of the problem.

While out at the range, I spent 40 rounds trying to sight in a red-dot scope at 50 yards.  On the 42 round, the buffer pin popped out.  The bolt and carrier would not engage fully forward. I opened up the rifle and found the sheared buffer pin and spring.  (the repeating problem) I have gone through 4 buffer pins so far this year, so I had luckily brought a spare.  After replacing the buffer pin and worked on the second problem.  A live round chambered, with the bolt not fully engaged.  (current problem) I tried the forward assist.  No luck.  I tried to pull the bolt and bolt carrier out to try and remove the live round.  Jammed.  I separated the lower receiver from the upper and packed it up for the long depressing drive home from the range.

1.  Why does the buffer pin always pop out?
2.  What the hell am I going to do with a live round jam?

Are there any smithies out there that can help?  (Without giving me any sh*t for buying a 7.62x39 upper?)  I'm sure I left out something you need to answer the question so tell me what you need.  I don't know what to do with a live round jam. I think that if I lubricate the bolt carrier and barrel extension teeth it would help free the round.  I dunno.

Thanks guys.

ConLima

ConLima

No grielf about the 7.62x39 decision I own 3 which all function perfectly. However, only the Colt sporter did not require substantial patients and tweaking.

Try this extraction method. Keeping in mind you have a live round chambered, in a safe location, making sure you remain clear of the muzzle, kneel down point the weapon straight up a firmly strike the but stock on the ground. If you happen to be on a hard surface, place a folded towel on the pavement to protect the butt plate.If this fails after one or two attempts, remove spring and buffer. Reassemble the upper to the lower and repeat above.

I have never seen this method fail to free the carrier. Often you will rip the rim off the case. If so tap round out with cleaning rod.

On your reoccuring problem of shearing off the buffer retaing spring. Are you sure you have the correct buffer/spring combination for a carbine and in particular the correct spring? It seems as if the buffer may be retaining too much energy at the end of the cycle. Perhaps you have a spring from a full length but stock. The springs in my carbines have 43 turns if that is usefull for a refrence.

Second is an assembly question. Is the tube screwed in far enough to capture the shoulder of the pin. Or putanother way, if you remove the spring and buffer does the shoulder of the pin remain flush with the receiver?

Another possiblity is the bolt carrier. Examine the bottom of hte bolt carrier and make sure there is a square "key way" machined in the carrier. As the bolt travels rearward it should not strike the retaing pin. You can check this visualy by bemoving the stock and tube then watch the pin as you cycle the bolt.

let us know what happens. feel free to contact me if this dosen't work or you have other specific 7.62 issues.

DanS

More Info:

The buffer spring that came with the 7.62x39 kit has 40 ring cycles.  I think I have the right spring but I will check with online catalogs to see if the picture is the same. The sheared buffer pin looks like it was contacted by the bolt carrier.  This could have been after it popped inside the receiver but I think that it was contacted while seated.  The reason I believe this is because there was a dent in the buffer tube where the tube meets the buffer pin.  I had to tool this back to being flush with the rest of the lip of the tube twice before.

I will check the bolt carrier and it's motion over the buffer pin. (As soon as I can clear the jam in a safe place)

If anyone has time: Please send links to proper buffer and spring for CAR stock if you have some handy.

Thanks!

Your buffer tube isn't screwed in far enough to engage enough of the buffer detent. Most likely, just guessing,  the threads on your lower receiver extension are not timed and it lacks the timing lip found on a correct part.

Timed threads (ala Colt) ensure that the tube goes in far enough to grab the detent, but not so far as to strike the upper and still allow the stock mounting ridge to wind up at 6 o-clock. The timing lip is a small protrusion on the front face (where the buffer sits) of the tube at the six o-clock position that grabs the detent.

This is assuming that your buffer detent hole is correctly located.

For the failure to lock I'd send it back to Model 1 as it could be anything. What kind of ammo were you shooting?

>> What kind of ammo were you shooting?

I went through a box of American Eagle Centerfire Rifle, 7.62 x 39 Soviet, 124 Grains, Full Metal Jacket and then sent 5 rounds of Silver Bear 122 grain FMJ when the pin popped.  Right after, the jam happened.  (Red flag. I know) The jam may be from laquer, but was the pin pop from 122 grain FMJ?  I have used the new Zimbabwe "Cheatah" ammo and my AR loved it - no problems.

ConLima

Simple fix. Take the buffer detent out. It is only there to keep the buffer from jumping out at you when you open the receivers up.
cruizer

I have to second the buffer tube needs to fitted right. The buffer tube holds the buffer detent to the correct tolerance.
Also a second to "hitting the butt of the rifle to open the bolt". If you break anything hitting the butt to open the bolt from chamber, that part that broke, doesn't belong on a personal defence firearm. IMO

UPDATE:

Well, the bolt carrier came loose and left the spent round in the chamber (stuck tight).  I know, I know, try the cleaning rod down the barrel trick.  No such luck.  That American Eagle catridge is seized in there.  I don't want to scratch/harm the interior of the barrel so what the hell can I use to extract this shell?  The cartridge is fully intact after the extractor was release from it.  Is there a full shell extractor tool?

(any ideas?)

IM sent.

What kind of mags were you using?