AR chewing up my buffer, any help?

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[ARCHIVED THREAD] - AR chewing up my buffer, any help?

Posted: 3/28/2006 1:25:11 PM EDT

here are some pics

Posted: 3/28/2006 1:26:45 PM EDT

[#1]

Posted: 3/28/2006 1:38:49 PM EDT

[#2]

HOLY hock.gif!

Posted: 3/28/2006 5:04:07 PM EDT

[#3]

I don't think I'll be able to help you other than to say that I think there are serious gouges in the lower. Never seen anything so bad.

Posted: 3/28/2006 6:48:07 PM EDT

[#4]

when you close your upper onto your lower do you see the back of the bolt carrier make contact with, and push slightly back, on the buffer right before the upper closes on the lower??

on an "in-spec" lower, the bolt carrier should push the buffer off of direct contact with the retaining pin.

check the back of the bolt carrier also for burrs or rough edges that might be making those marks.

Posted: 3/28/2006 8:00:43 PM EDT

[#5]

Looks like it is hitting the retaining pin, either that or you have a chipmunk in the reciever.

The buffer should be kept from hitting the pin by the carrier during operation, the pin should only touch it when you open her up, to prevent it from launching out.

Posted: 3/29/2006 3:02:14 PM EDT

[#6]

Whose carrier are you using? Definitely seems the buffer is hitting the retaining pin. I am wondering if your carrier is out of spec?

Posted: 3/29/2006 3:31:28 PM EDT

[#7]

I had that same problem, it was the carrier on mine.

Posted: 3/29/2006 4:00:52 PM EDT

[#8]

Quoted:
Looks like it is hitting the retaining pin, either that or you have a chipmunk in the reciever.
quote]

Posted: 3/30/2006 5:38:52 AM EDT

[#9]

Quoted:
I had that same problem, it was the carrier on mine.

My thoughts too,

Back/bottom of the carrier at the relief slot channel for the buffer retain pin should have a nice protruding bur that causing the damage to the buffer face.

Posted: 3/30/2006 8:15:32 AM EDT

[#10]

Quoted:
Quoted:
I had that same problem, it was the carrier on mine.

My thoughts too,

Back/bottom of the carrier at the relief slot channel for the buffer retain pin should have a nice protruding bur that causing the damage to the buffer face.

it feels a little sharp at the bottom where it is cut, maybe thats the problem?

eventually will it wear in?? or just keep abusing the buffer?

Posted: 3/30/2006 9:15:19 AM EDT

[#11]

For me, it was an out of spec lower receiver. Try a different upper receiver (w/ a different bolt carrier group) and a "new" buffer. Try cycling it a few times and really let the bolt slam home by itself a few times. Inspect the buffer. If it has a few marks, the lower receiver is out of spec. The buffer retainer hole was drilled too close to the end of the lower receiver not allowing the buffer to peek out enough.

Posted: 3/30/2006 11:09:19 AM EDT

[#12]

Quoted:
Quoted:
Quoted:
I had that same problem, it was the carrier on mine.

My thoughts too,

Back/bottom of the carrier at the relief slot channel for the buffer retain pin should have a nice protruding bur that causing the damage to the buffer face.

it feels a little sharp at the bottom where it is cut, maybe thats the problem?

eventually will it wear in?? or just keep abusing the buffer?

You have a hardened steel carrier against an aluminum buffer. You're seeing what is going to give, and must use a file to knock down the bur on the back of the carrier to correct the problem

As for the buffer contacting the buffer retaining pin, if this was happening, you would see oblong'g in the buffer retainer front hole side, or the post of the retaining pin being bent. If neither of these sign present themselves, the suspect that the carrier bur is to blame.

Posted: 3/30/2006 11:18:39 AM EDT

[#13]

I'm not sure Dano, but that looks just like the buffer slamming against the retainer.

Original poster: Can you take a sideway photo of the buffer? See if the buffer protrudes away from the receiver. In other words, going from the top of the deck (where the charging handle slides on, should have 2 wear marks there) towards the shelf where the upper receiver sits, the buffer SHOULD visibly protrude. When shotgunning the receivers, gently close the upper and take notice of the bolt carrier mating with the buffer. It should gently kiss the buffer and push it in.

In my out of spec lower, the buffer did NOT protrude and the carrier did NOT kiss the buffer and push it in gently. After a few cycles, my buffer looked sort of like yours but not as bad.

Posted: 3/30/2006 11:20:17 AM EDT

[#14]

It is doing the same thing as my Superior Arms lower. The problem is that the buffer retaining pin is too far back and the buffer is contacting the pin every time it comes forward instead of following the bolt carrier forward. It isn't a Superior lower is it?

Posted: 3/31/2006 8:27:27 AM EDT

[#15]

Oh man that's horrible.

Posted: 3/31/2006 9:18:33 AM EDT

[#16]

Could be that your buffer tube is not securely tightened. When you installed the buffer tube did you push the retaining pin down as you were tightening? The retaining pin should be held in place by the buffer tube. Ill venture to guess that the retaining pin is not moving freely and is being held by the buffer tube preventing the tube from being tightened completely.

Posted: 3/31/2006 9:45:45 AM EDT

[#17]

It is obvious what is wrong.

Posted: 3/31/2006 10:42:47 AM EDT

[#18]

The buffer should only hit the retainer pin when you remove the upper, when you close the receivers, it should pushed back by the BCG. What brand are the parts? And what happened to the lower?

Posted: 3/31/2006 12:03:23 PM EDT

[#19]

I will re-post this question because it wasn't answered:

"when you close your upper onto your lower do you see the back of the bolt carrier make contact with, and push slightly back, on the buffer right before the upper closes on the lower??"

If you would check this it might all make sense.

Posted: 4/3/2006 9:27:50 AM EDT

[#20]

Quoted:
It is doing the same thing as my Superior Arms lower. The problem is that the buffer retaining pin is too far back and the buffer is contacting the pin every time it comes forward instead of following the bolt carrier forward. It isn't a Superior lower is it?

yes actually it is!

Posted: 4/3/2006 9:28:31 AM EDT

[#21]

Quoted:
I will re-post this question because it wasn't answered:

"when you close your upper onto your lower do you see the back of the bolt carrier make contact with, and push slightly back, on the buffer right before the upper closes on the lower??"

If you would check this it might all make sense.

just barely.

Posted: 4/3/2006 9:40:53 AM EDT

[#22]

Quoted:
Quoted:
It is doing the same thing as my Superior Arms lower. The problem is that the buffer retaining pin is too far back and the buffer is contacting the pin every time it comes forward instead of following the bolt carrier forward. It isn't a Superior lower is it?

yes actually it is!

IM sent.

Posted: 4/8/2006 12:59:09 PM EDT

[#23]

I am having the same issue on a Superior lower. I have two such lowers; a blem and an unblemished. I have tried different combinations trying to determine the culprit. One upper(an A2 with an "M" next to the rear sight) appears to cause the "dents". This upper has 2k rounds through it.

I am reluctant to call the blemmed lower "bad" (i.e. improper buffer pin placement).

Ideas? Suggestions? Input please.

Posted: 4/8/2006 1:04:59 PM EDT

[#24]

I've seen that many times and every time the buffer retaining pin is in the wrong place, your lower is out of spec, measure where your retaining pin hole is

Posted: 4/9/2006 8:15:41 AM EDT

[#25]

If the buffer retaining pin hole is in the wrong place and tearing up your buffer, it's ok to take it out. The pin's only purpose is to hold back the buffer when you break open the receivers. When it's closed up, the pin doesn't touch anything (when the hole is in the right place) and the gun functions normally. If you take it out, you just need to stop the buffer with your thumb when you start lifting the upper from the lower. I usually don't open up the range ARs in use except to clean them, and I always take out the buffer to wipe it off anyway. Some of the 3-gun guys do this after having the pin break off and get wedged in the works.

Anyway, it's a way to use your "bad" receiver without tearing up your buffer.

Posted: 4/9/2006 11:16:46 AM EDT

[#26]

To any of those reading this thread:
We at Superior Arms unconditionally stand behind our product. If you have one of our lowers and you have this issue please contact us and we will exchange it. I will say we made an adjustment for issues related back by customers on marking the buffer. Call us directly, email or IM me, we want to make it right with you.

Leo Williams
Superior Arms
836 Weaver Blvd.
Wapello, IA 52653
319-523-2016
www.superiorarms.com

Posted: 4/10/2006 1:52:24 AM EDT

[#27]

Well that's very cool.

Will the replacemnt lowers have the same serial numbers?

Posted: 4/10/2006 3:08:45 AM EDT

[#28]

Back when I assembled my first AR in 1987 I used an Essential Arms lower (cast aluminum) and it's buffer retainer hole was machined too far to the rear and would eat up my buffer. It was replaced under warranty.

[ARCHIVED THREAD] - AR chewing up my buffer, any help?

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